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14,233 Posts
Very tidy!
1972 TR6RV Project
61 - 80 of 92 Posts
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14,233 Posts
Great minds think alike.
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440 Posts
Amal Carburetter O-Rings
Pictured below is my carb mounting.
I’m using a 2.5mm x 34mm viton ring for the flange groove,
And 4mm x 6mm viton rings for the fixing studs along with the stock 70-9555 cups
With this ring combination, I set the gap between carb flange and manifold at .050”
By my calculations there are 3 different O-Rings that will work in the flange groove.
This may be well-known information to some, but I was frustrated by a carb gasket kit that came from a trusted supplier with a 2.5x35mm flange O-ring that didn’t fit in the groove, so I decided to take my own measurements.
On my desk are 600 and 900 series carbs. They both have the same ring groove.
1.518 large dia x 1.372 small dia, for an effective mean diameter of 1.445” or 36.7mm
So, 1.445” (36.7mm) is what we ideally want for the mean diameter of our ring.
The groove is .073” wide x .050” deep.
Solution 1: #028 ring 1/16” x 1 3/8”, effective mean diameter 1.437” or 36.5mm (comes with carb)
Solution 2: Metric 2.5 x 34 ring, effective mean diameter 36.5mm or 1.437” (Goldilocks’ choice)
Solution 3: #219 ring 1/8” x 1 5/16”, effective mean diameter 1.437” or 36.5mm (needs longer studs)
I got the M2.5x34 viton rings at an industrial supply for $7.36 for a pack of 5
![Motor vehicle Engineering Gas Machine tool Machine]()
Pictured below is my carb mounting.
I’m using a 2.5mm x 34mm viton ring for the flange groove,
And 4mm x 6mm viton rings for the fixing studs along with the stock 70-9555 cups
With this ring combination, I set the gap between carb flange and manifold at .050”
By my calculations there are 3 different O-Rings that will work in the flange groove.
This may be well-known information to some, but I was frustrated by a carb gasket kit that came from a trusted supplier with a 2.5x35mm flange O-ring that didn’t fit in the groove, so I decided to take my own measurements.
On my desk are 600 and 900 series carbs. They both have the same ring groove.
1.518 large dia x 1.372 small dia, for an effective mean diameter of 1.445” or 36.7mm
So, 1.445” (36.7mm) is what we ideally want for the mean diameter of our ring.
The groove is .073” wide x .050” deep.
Solution 1: #028 ring 1/16” x 1 3/8”, effective mean diameter 1.437” or 36.5mm (comes with carb)
Solution 2: Metric 2.5 x 34 ring, effective mean diameter 36.5mm or 1.437” (Goldilocks’ choice)
Solution 3: #219 ring 1/8” x 1 5/16”, effective mean diameter 1.437” or 36.5mm (needs longer studs)
I got the M2.5x34 viton rings at an industrial supply for $7.36 for a pack of 5
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440 Posts
Before my next bike post I'd like to point out that Appalachian harmonies are the best, with Black Gospel running a close second
(2674) Louvin Brothers - I Don't Believe You've Met My Baby - YouTube
(2675) Gillian Welch & David Rawlings - I Want To Sing That Rock And Roll - YouTube
(2674) Louvin Brothers - I Don't Believe You've Met My Baby - YouTube
(2675) Gillian Welch & David Rawlings - I Want To Sing That Rock And Roll - YouTube
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440 Posts
Okay now on to the air filter.
The stock one is non-functional. It’s a factory feature.
Oh, plenty of air flow, but air filled with dirt seeping through the seams.
I hated it in ‘73 and I hate it now.
I like riding on dirt roads. On my ride tonight I could have ridden pavement 90% of the way, but what fun is that?
Yes, I'm actually riding the bike now and catching this journal up from a couple-three weeks ago.
The Bonneville ducts through the air filter covers but the Tiger ducts through the center castings so in order to access the carb, you have to take everything apart.
It takes a while to do that and even longer to put it back together. Yes, I reiterate, it sucks.
So luckily, the old TR6 type pan filter will work on the OIF.
It has to be assembled piece by piece, but it is a far easier process than the stock one.
I made it easier in a couple of ways.
I tossed the hose clamp that came with it in the garbage and utilized the stock slim ring clamp that held the old rubber boot on the carb mouth. (60-3975 Clip, Jubilee Type). I removed the 2BA Philips head and found that a M4 threads into it without re-tapping.
So, I bought a stainless M4 socket head cap screw which can be tightened with a ball-driver type M3 allen wrench, hence the angular approach with the tightening tool is no problem.
The chrome shroud needs to be partially unwrapped to get it on, so I pop-riveted the keeper clamps to the shroud so I wasn’t fumbling around with them.
I also discarded the cheap screw and nut that was on it and used a stainless M4 socket head cap screw on it as well.
So, I only need one tool in my kit, an M3 long arm balldriver.
Future improvement will be to solder a little piece of steel where the nut goes and tap it to M4. Oh I can see very easily how I’d lose that nut and be kicking myself.
![Automotive tire Motor vehicle Hood Automotive design Automotive lighting]()
The stock one is non-functional. It’s a factory feature.
Oh, plenty of air flow, but air filled with dirt seeping through the seams.
I hated it in ‘73 and I hate it now.
I like riding on dirt roads. On my ride tonight I could have ridden pavement 90% of the way, but what fun is that?
Yes, I'm actually riding the bike now and catching this journal up from a couple-three weeks ago.
The Bonneville ducts through the air filter covers but the Tiger ducts through the center castings so in order to access the carb, you have to take everything apart.
It takes a while to do that and even longer to put it back together. Yes, I reiterate, it sucks.
So luckily, the old TR6 type pan filter will work on the OIF.
It has to be assembled piece by piece, but it is a far easier process than the stock one.
I made it easier in a couple of ways.
I tossed the hose clamp that came with it in the garbage and utilized the stock slim ring clamp that held the old rubber boot on the carb mouth. (60-3975 Clip, Jubilee Type). I removed the 2BA Philips head and found that a M4 threads into it without re-tapping.
So, I bought a stainless M4 socket head cap screw which can be tightened with a ball-driver type M3 allen wrench, hence the angular approach with the tightening tool is no problem.
The chrome shroud needs to be partially unwrapped to get it on, so I pop-riveted the keeper clamps to the shroud so I wasn’t fumbling around with them.
I also discarded the cheap screw and nut that was on it and used a stainless M4 socket head cap screw on it as well.
So, I only need one tool in my kit, an M3 long arm balldriver.
Future improvement will be to solder a little piece of steel where the nut goes and tap it to M4. Oh I can see very easily how I’d lose that nut and be kicking myself.
Nice job, I fitted the same to my 76 Tiger, I could fit it in one piece until I fitted new gaskets to the manifold, after that I lost a little clearance and it’s now piece by piece as you say.
I also used a narrow hose clip, it’s a stainless one made by Norma that I can tighten with a 6mm spanner. Good idea riveting the little clamping pieces on, they’re a right fiddle.
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440 Posts
;-) Thanks, I was pretty frustrated and thought "there's got to be a better way"
I'm holding the shroud closed with zip ties while I get the bolt in it. There's got to be a better way for that too, but I haven't thought of it
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440 Posts
Side Covers
I got the Fiberglas side covers from Lowbrow Customs and I think they’re very well made.
However, it’s not like you’re going to bolt them on out of the box – you’re going to be doing some carving. Well actually I did everything with a handheld pneumatic belt sander, a battery powered drill, and a Dremel tool. And it took me awhile because I very incrementally worked them in.
Shown in the first picture is my bike, which is a Low Frame 72 Tiger. Some people prefer the High Frame, but I like the Low. Any argument that a low center of gravity is not a good thing? Anyway, I say all this because the side covers have 2 holes in them out of the box and they might fit some bikes but not mine. The front one ended up being perfect, but I had to drill and carve a new hole for the back rubber mounts. It uses the original factory rubbers, so I bought two new ones.
![Wheel Tire Fuel tank Automotive fuel system Vehicle]()
Your best friend in this pursuit will be a red grease pencil to mark where you want to drill and carve, being that when you’re done you just wipe it off.
Right off the bat I found that these things need to be pushed in tight or your seat won’t open. I think they look better like that too. That sexy Triumph “Wasp Waist” is enhanced by following the contour of the frame.
![Hood Automotive tire Motor vehicle Automotive design Bumper]()
![Tire Wheel Fuel tank Automotive fuel system Vehicle]()
Where to start is by holding the cover where you think it looks best (because again, these frames vary) and drawing a line with your grease pencil in line with the rear studs that your grommets are going to push onto. Do this several times until you get a repeatable line that you’re happy with. A side note would be to clean up that stud with a file and sandpaper because for example mine had weld spatter. We’re assuming that the existing front hole in the side cover is good enough where it is.
Now wrap that line around the back end of the cover and mark a centerline such that the ½” hole for the grommet will be nearly flush with the inside of the cover. Using a metal scribing compass or divider, draw a ½” circle there. Run a 1/8” drill through so you can measure edge distance etc. before proceeding. Next drill the hole to ¼” if you’re happy with the location. Now with a Dremel tool and a fine carbide burr open your hole up such that the ½” grommet fits. I had to fiddle a bit with this until I was happy that it was going straight in.
Now with the grommet in, you can try fitting the cover. Guess what, it won’t go because it’ll hit your fender or something else like a seat hinge of frame fitting. Bring your trusty grease pencil into the fray and mark where it hits and carve away a little at a time. Oh this took me forever, but I finally got it.
Bear in mind that on the drive side, you need to leave ample room for your wiring harness and plug leads to prevent chafing. Also, that chainguard moves up as the suspension does so give yourself some clearance there. Carve around the crankcase breather as needed.
![Motor vehicle Automotive tire Hood Vehicle Automotive design]()
![Land vehicle Tire Fuel tank Wheel Vehicle]()
On the timing side, mine has a key in the original cover and my harness terminates there so I wanted to keep it that way. I used the original Lucas switch and, in my case, (maybe not yours) there was space for the switch 2 ¼” away from the frame directly in line with the stud. Again, I used a metal scribing divider to mark off the location for the hole with 2 flats to fit the key switch.
![Tire Wheel Automotive lighting Motorcycle Motor vehicle]()
I had to make up some space on the front screw mount because there was about a ¼” gap so I bought some adhesive backed rubber and used my scissors and a hole punch to make up the spacers as needed.
https://www.amazon.com/gp/product/B09S8Y1CBM
I bolted the cover on with a 5/16-24 x 1” stainless hex head.
Using a 5/16" x 1" OD Stainless Steel EPDM Bonded Sealing Neoprene Rubber Washer with that bolt, a rubber sandwich was created for the mount.
https://www.amazon.com/gp/product/B09YCCQ1ZR
I got the Fiberglas side covers from Lowbrow Customs and I think they’re very well made.
However, it’s not like you’re going to bolt them on out of the box – you’re going to be doing some carving. Well actually I did everything with a handheld pneumatic belt sander, a battery powered drill, and a Dremel tool. And it took me awhile because I very incrementally worked them in.
Shown in the first picture is my bike, which is a Low Frame 72 Tiger. Some people prefer the High Frame, but I like the Low. Any argument that a low center of gravity is not a good thing? Anyway, I say all this because the side covers have 2 holes in them out of the box and they might fit some bikes but not mine. The front one ended up being perfect, but I had to drill and carve a new hole for the back rubber mounts. It uses the original factory rubbers, so I bought two new ones.
Your best friend in this pursuit will be a red grease pencil to mark where you want to drill and carve, being that when you’re done you just wipe it off.
Right off the bat I found that these things need to be pushed in tight or your seat won’t open. I think they look better like that too. That sexy Triumph “Wasp Waist” is enhanced by following the contour of the frame.
Where to start is by holding the cover where you think it looks best (because again, these frames vary) and drawing a line with your grease pencil in line with the rear studs that your grommets are going to push onto. Do this several times until you get a repeatable line that you’re happy with. A side note would be to clean up that stud with a file and sandpaper because for example mine had weld spatter. We’re assuming that the existing front hole in the side cover is good enough where it is.
Now wrap that line around the back end of the cover and mark a centerline such that the ½” hole for the grommet will be nearly flush with the inside of the cover. Using a metal scribing compass or divider, draw a ½” circle there. Run a 1/8” drill through so you can measure edge distance etc. before proceeding. Next drill the hole to ¼” if you’re happy with the location. Now with a Dremel tool and a fine carbide burr open your hole up such that the ½” grommet fits. I had to fiddle a bit with this until I was happy that it was going straight in.
Now with the grommet in, you can try fitting the cover. Guess what, it won’t go because it’ll hit your fender or something else like a seat hinge of frame fitting. Bring your trusty grease pencil into the fray and mark where it hits and carve away a little at a time. Oh this took me forever, but I finally got it.
Bear in mind that on the drive side, you need to leave ample room for your wiring harness and plug leads to prevent chafing. Also, that chainguard moves up as the suspension does so give yourself some clearance there. Carve around the crankcase breather as needed.
On the timing side, mine has a key in the original cover and my harness terminates there so I wanted to keep it that way. I used the original Lucas switch and, in my case, (maybe not yours) there was space for the switch 2 ¼” away from the frame directly in line with the stud. Again, I used a metal scribing divider to mark off the location for the hole with 2 flats to fit the key switch.
I had to make up some space on the front screw mount because there was about a ¼” gap so I bought some adhesive backed rubber and used my scissors and a hole punch to make up the spacers as needed.
https://www.amazon.com/gp/product/B09S8Y1CBM
I bolted the cover on with a 5/16-24 x 1” stainless hex head.
Using a 5/16" x 1" OD Stainless Steel EPDM Bonded Sealing Neoprene Rubber Washer with that bolt, a rubber sandwich was created for the mount.
https://www.amazon.com/gp/product/B09YCCQ1ZR
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1,265 Posts
This is so good, I've gone back for another look. The fuse holder is neat. Do you have a link, so I can find a similar one?
Thanks Flick.
You've persuaded me to splash out on rubber grommets too
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440 Posts
Hi Fledge,
Here you go
Fuse holder: https://www.amazon.com/gp/product/B00OK9H3EI
Grommets: https://www.amazon.com/gp/product/B09H7P5DPY
Thank you, I've built a lot of special machines, and anything less than this quality would be frowned upon by our customers. We also routinely had to pack a lot of stuff into a tight space. If we failed to make it pretty, it got labeled 10 lbs. of sh*t in a 5 lb. bag
Those fuse holders are really neat, didn’t catch that detail before.
Here’s one on eBay, Amazon is showing out of stock.
Here’s one on eBay, Amazon is showing out of stock.
PANEL Mount 12V 10A STANDARD BLADE IN LINE FUSE HOLDER EARS wth SPADE CONNECTORS | eBay
With ears for installation.
www.ebay.co.uk
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440 Posts
Spark Plugs:
My Workshop Manual Says Champion N3 with a .025 gap so that’s what I did. (N3C actually)
They’re a readily available plug at just about every hardware store.
Runs really well but still short miles.
My other bikes (6T and T100R) are running NGK B8ES and running nicely. Their manuals state Champion N4.
I did a little poking around about spark plug opinions and sheesh, it’s about the same as an oil discussion. Funny the things people will get worked up over.
I did glean this tidbit though:
NGK Higher the number=colder plug
Champion: Lower the number=colder plug
My Vape instruction manual says to use copper plug wires with 5K ohm resistor caps.
I made up my own plug leads
I bought 50’ of American made 7mm copper plug wire and I used some right-angle coil caps I had laying around from another build
NGK makes some really nice resistor caps that just screw into the end of a cut plug lead. They have rubber boots at each end and look sharp: NGK# LB05EP shown
NGK also makes a variety of plug caps. 8381 LZFH, for example is non-resistor.
I would assume that if you are using resistor plugs you would use a non-resistor cap. Somebody correct me if I’m wrong.
Addendum: NGK Plug Cap Reference Guide NGK_Resistor_Covers.pdf (sparkplugs.com)
![Automotive tire Motor vehicle Vehicle Automotive lighting Automotive design]()
My Workshop Manual Says Champion N3 with a .025 gap so that’s what I did. (N3C actually)
They’re a readily available plug at just about every hardware store.
Runs really well but still short miles.
My other bikes (6T and T100R) are running NGK B8ES and running nicely. Their manuals state Champion N4.
I did a little poking around about spark plug opinions and sheesh, it’s about the same as an oil discussion. Funny the things people will get worked up over.
I did glean this tidbit though:
NGK Higher the number=colder plug
Champion: Lower the number=colder plug
My Vape instruction manual says to use copper plug wires with 5K ohm resistor caps.
I made up my own plug leads
I bought 50’ of American made 7mm copper plug wire and I used some right-angle coil caps I had laying around from another build
NGK makes some really nice resistor caps that just screw into the end of a cut plug lead. They have rubber boots at each end and look sharp: NGK# LB05EP shown
NGK also makes a variety of plug caps. 8381 LZFH, for example is non-resistor.
I would assume that if you are using resistor plugs you would use a non-resistor cap. Somebody correct me if I’m wrong.
Addendum: NGK Plug Cap Reference Guide NGK_Resistor_Covers.pdf (sparkplugs.com)
You are correct, with an electronic ignition you need one or the other but not both. I’ve had very good results with those particular NGK caps on KTM singles which are prone to ruining plug caps., I suggest a dab of silicon dielectric grease on the end of the wire before screwing in to keep out the moisture. Although there’s a rubber boot, heat cycling can draw in moisture which is then trapped.
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11,929 Posts
Hi,
. Analogue electronics - Lucas Rita, Boyer-Bransden Mark-anything (commonly Mk.3 or Mk.4), Pazon Sure-Fire, Wassell - don't "need" any additional HT resistance.
. Digital electronics - Tri-Spark, Boyer-Bransden MicroDigital and MicroPower, Pazon Smart-Fire and Altair, other digital electronic gadgets - do need some additional HT resistance; however, it's worth understanding more than any EI maker's information:-
.. resistive spark plugs, caps and HT leads are typically 5 KOhms (5,000 Ohms) each;
.. coil with a single HT lead needs one or the other, more than one is not 'better', or even 'good' - the air gap between a plug's electrodes is many, many time more resistive, resistances connected 'in series' are cumulative, the more you connect, the more risk there is the HT will find an alternative path to 'earth'; if that alternative path happens to be through the box (due to iffy insulation somewhere?) you can kiss the electronics goodbye.
The EI makers are even less informative on HT resistance on twin-HT-lead coils. Their HT circuit is wholly independent of the LT - do they need two resistors (10 Kohms), or just one (5 KOhms); say one resistor plug and one without?
Ime, they aren't, persistent pita and they're a crap idea:-
. Certainly 1970's Triumph plug leads had the plug terminal crimped to the lead, the "plug cap" was just a plastic cover over the connection to the plug itself.
. Otoh, as you've posted, NGK plug caps screw into the end of the HT lead - immediately one extra connection in a conductor carrying 15-20(?) KV many times a second ...
. However, it's worse than that, there's two additional connections within the cap - one each end of the internal resistor ...
. When (not if ime) screw-in plug caps come loose from the plug lead, the poor connection becomes an additional source of electro-magnetic interference - the very thing any additional HT resistance is there to attenuate ...
If a bike must have additional HT resistance to attenuate electro-magnetic interference with digital electronics on the bike, the most long-term reliable combination I've found is the aforementioned 1970's-type Triumph plug leads with resistor plugs.
Hth.
Regards,
+1.
Not so correct:-
. Analogue electronics - Lucas Rita, Boyer-Bransden Mark-anything (commonly Mk.3 or Mk.4), Pazon Sure-Fire, Wassell - don't "need" any additional HT resistance.
. Digital electronics - Tri-Spark, Boyer-Bransden MicroDigital and MicroPower, Pazon Smart-Fire and Altair, other digital electronic gadgets - do need some additional HT resistance; however, it's worth understanding more than any EI maker's information:-
.. resistive spark plugs, caps and HT leads are typically 5 KOhms (5,000 Ohms) each;
.. coil with a single HT lead needs one or the other, more than one is not 'better', or even 'good' - the air gap between a plug's electrodes is many, many time more resistive, resistances connected 'in series' are cumulative, the more you connect, the more risk there is the HT will find an alternative path to 'earth'; if that alternative path happens to be through the box (due to iffy insulation somewhere?) you can kiss the electronics goodbye.
The EI makers are even less informative on HT resistance on twin-HT-lead coils. Their HT circuit is wholly independent of the LT - do they need two resistors (10 Kohms), or just one (5 KOhms); say one resistor plug and one without?
Ime, they aren't, persistent pita and they're a crap idea:-. Certainly 1970's Triumph plug leads had the plug terminal crimped to the lead, the "plug cap" was just a plastic cover over the connection to the plug itself.
. Otoh, as you've posted, NGK plug caps screw into the end of the HT lead - immediately one extra connection in a conductor carrying 15-20(?) KV many times a second ...
. However, it's worse than that, there's two additional connections within the cap - one each end of the internal resistor ...
. When (not if ime) screw-in plug caps come loose from the plug lead, the poor connection becomes an additional source of electro-magnetic interference - the very thing any additional HT resistance is there to attenuate ...
If a bike must have additional HT resistance to attenuate electro-magnetic interference with digital electronics on the bike, the most long-term reliable combination I've found is the aforementioned 1970's-type Triumph plug leads with resistor plugs.
Hth.
Regards,
Joined
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440 Posts
Thanks Stuart.Hi,
+1.
Not so correct:-
. Analogue electronics - Lucas Rita, Boyer-Bransden Mark-anything (commonly Mk.3 or Mk.4), Pazon Sure-Fire, Wassell - don't "need" any additional HT resistance.
. Digital electronics - Tri-Spark, Boyer-Bransden MicroDigital and MicroPower, Pazon Smart-Fire and Altair, other digital electronic gadgets - do need some additional HT resistance; however, it's worth understanding more than any EI maker's information:-
.. resistive spark plugs, caps and HT leads are typically 5 KOhms (5,000 Ohms) each;
.. coil with a single HT lead needs one or the other, more than one is not 'better', or even 'good' - the air gap between a plug's electrodes is many, many time more resistive, resistances connected 'in series' are cumulative, the more you connect, the more risk there is the HT will find an alternative path to 'earth'; if that alternative path happens to be through the box (due to iffy insulation somewhere?) you can kiss the electronics goodbye.
The EI makers are even less informative on HT resistance on twin-HT-lead coils. Their HT circuit is wholly independent of the LT - do they need two resistors (10 Kohms), or just one (5 KOhms); say one resistor plug and one without?
. Certainly 1970's Triumph plug leads had the plug terminal crimped to the lead, the "plug cap" was just a plastic cover over the connection to the plug itself.
. Otoh, as you've posted, NGK plug caps screw into the end of the HT lead - immediately one extra connection in a conductor carrying 15-20(?) KV many times a second ...
. However, it's worse than that, there's two additional connections within the cap - one each end of the internal resistor ...
. When (not if ime) screw-in plug caps come loose from the plug lead, the poor connection becomes an additional source of electro-magnetic interference - the very thing any additional HT resistance is there to attenuate ...
If a bike must have additional HT resistance to attenuate electro-magnetic interference with digital electronics on the bike, the most long-term reliable combination I've found is the aforementioned 1970's-type Triumph plug leads with resistor plugs.
Hth.
Regards,
This is an area in which I'm not very well versed
I used to build industrial electronic systems and noise was the bane of our existence
We followed the component manufacturers shielding specs (sometimes at the source, sometimes at the destination) to the letter and that was always a good start
But even then. issues could crop up, so a handy solution was to wrap the offending noisy cable's conductors in a ferrite toroid.
I do possess a plug lead crimper, and resistor plugs are certainly widely available
And yes, my 62 6T with a Boyer IV, non-resistor caps and plugs runs great
Joined
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440 Posts
Heard this for the first time today. Damn it's beautiful
(2836) Arlo McKinley - "Stealing Dark from the Night Sky" (Official Video) - YouTube
(2836) Arlo McKinley - "Stealing Dark from the Night Sky" (Official Video) - YouTube
Joined
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440 Posts
Ignition:
Update - I’ve ridden the bike close to 400 miles now and everything seems great, so riding is kind of getting in the way of writing.
I installed the Wassell Vape electronic ignition.
Since I have a brand-new wiring harness, I utilized the existing ignition wires in it.
I found that I had a faulty crimp in one of the connectors I put on coming out of the timing cover, so I took them off and used marine rated waterproof butt connectors and slid some black shrink tube over them to pretty them up.
Lining up the Vape stator and rotor scribe marks, the bike started and seemed pretty good, so I took it for a short ride.
At low RPM it coughed a little under load but around 2000 rpm it seemed much better.
Even though I got those scribe marks as close as I could by eye, turns out timing was around 6-8 degrees retarded.
I know this because with my timing strobe the scribe on the alternator rotor was approx. 3/16 retarded.
The alternator rotor has a radius of 1.375 so the math here would be: arcsin (.188/1.375) = 7.8 degrees
The ignition stator is about the same diameter as the alternator rotor.
So, moving the ignition stator half of 3/16 put the strobe timing right on.
I found that full advance happened at approx. 4500 rpm with a very small amount between 4000 and 4500.
It would be interesting to put a degree wheel on it at some point and map the advance curve but at that point I was more excited about riding than statistics. Still am.
![Automotive tire Automotive lighting Motor vehicle Automotive design Alloy wheel]()
Update - I’ve ridden the bike close to 400 miles now and everything seems great, so riding is kind of getting in the way of writing.
I installed the Wassell Vape electronic ignition.
Since I have a brand-new wiring harness, I utilized the existing ignition wires in it.
I found that I had a faulty crimp in one of the connectors I put on coming out of the timing cover, so I took them off and used marine rated waterproof butt connectors and slid some black shrink tube over them to pretty them up.
Lining up the Vape stator and rotor scribe marks, the bike started and seemed pretty good, so I took it for a short ride.
At low RPM it coughed a little under load but around 2000 rpm it seemed much better.
Even though I got those scribe marks as close as I could by eye, turns out timing was around 6-8 degrees retarded.
I know this because with my timing strobe the scribe on the alternator rotor was approx. 3/16 retarded.
The alternator rotor has a radius of 1.375 so the math here would be: arcsin (.188/1.375) = 7.8 degrees
The ignition stator is about the same diameter as the alternator rotor.
So, moving the ignition stator half of 3/16 put the strobe timing right on.
I found that full advance happened at approx. 4500 rpm with a very small amount between 4000 and 4500.
It would be interesting to put a degree wheel on it at some point and map the advance curve but at that point I was more excited about riding than statistics. Still am.
Attachments
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440 Posts
Front Suspension:
Red ATF streaks on the front of my fuel tank were my clue that the seals were gone.
Before releasing the compression on the main springs by unscrewing the stanchion top cap nuts, I used a 7/32 hex bit in my battery powered drill set on torque-ratchet and spun the damper tube cap screws free. Then I pulled the fork legs off.
Opening up the fork legs revealed that a non-mechanical person had installed new seals at one point. The aluminum had pry bar marks, probably a screwdriver, and the seals seem to have been installed with red Loctite and they were a chore to get out of there without causing further damage.
The mouth of the seal bore hadn’t been chamfered or deburred from the factory, so I fixed that.
Damage that the previous owner had done was superficial and cleaned up okay with a file and sandpaper.
Inside the fork leg was an eighth inch of mud at the bottom, so I made a giant Q-Tip with a wooden dowel and some paper towels and got everything clean and washed out.
Next, the stanchion top cap nuts are removed, and the main springs withdrawn. Measuring the springs revealed they were to original spec length.
The only box end wrench I didn’t have in my tool kit was the 1 ¼” for the aluminum stanchion bottom end plug so I bought one.
Using an open-end wrench here would be disastrous as the aluminum deformed somewhat even with a box end wrench as I removed the plugs.
Again, somebody with a hard-on for red Loctite really went to town and coated it heavily.
![Vehicle Motor vehicle Automotive tire Automotive design Tire]()
When the bottom plugs come out, the whole damper assembly comes out. I very carefully cleaned up the threads on the bottom plug and inside the stanchion, and everybody got a good bath.
![Gun accessory Auto part Metal Gun barrel Gas]()
Inside the stanchion tubes was rusty so I used an extended flap tool with my pneumatic grinder to clean them up and then passed a kerosene-soaked towel through with a wooden dowel to be sure they were immaculate inside.
![Fuel tank Tire Automotive fuel system Vehicle Wheel]()
![Motor vehicle Automotive tire Automotive lighting Aircraft Automotive design]()
![Automotive tire Tool Gas Auto part Technology]()
I had already bought new seals and O-rings before I found out that there are high-end aftermarket components that can be used here to avail a more responsive action. I’d appreciate advice pertaining to this for future reference.
When I measured over the new damper valve O-ring as installed it seemed to be only about .001” greater diameter than the inside of the stanchion but indeed there is some stiction as is evidenced when raising the bike with a jack, the suspension extends in little stages instead of linearly.
After a thorough cleaning, I reinstalled the damper assemblies. Minimal red Loctite was used around a couple of threads on the bottom stanchion plug.
Next, instead of using the stock wipers, I slid on the new Commando gaiters from Andover Norton.
A dab of grease was used to hold the sealing washers on the end of the damper tubes and the fork legs slid on and the bottom socket head cap screws started.
I made up this whiz-bang special screwdriver from 22” of half-inch round steel stock and a hacksaw and file when I did the forks on my 72 Daytona, and it works here as well to hold the damper tube from turning while torquing the bottom cap screws.
![Automotive tire Finger Household hardware Rim Nickel]()
The drain plugs were then re-installed in the fork legs and the main springs were dropped in the stanchion tubes.
The spec for my bike reads 190cc of ATF but I used equal parts of 5 and 10 weight fork oil to achieve 7.5 weight.
Readily available fork oil for me was the Maxima brand.
The bottom diameter of the gaiter rubber is about a half inch smaller than the fork leg upper diameter, but with a heat gun applied (or even a hair dryer I would suspect), it becomes very stretchy and is easily slid down and over.
I found some stainless-steel zip ties at the hardware store that I think look nice next to the polished aluminum legs.
For the top I used black plastic zip ties, and you can barely notice they’re there.
After a quick trip around my local dirt roads the gaiters were indeed covered with road dust along the front so I’m glad I went for this upgrade.
Now that I’ve ridden about 600 miles of combined dirt and highway, they’re caked pretty good and need a wash, but my front suspension seems very nice.
Being I ride a lot of dirt and bumpy roads; I’m half tempted to try going down to 5 weight fork oil and see how it feels.
![Tire Wheel Automotive tire Light Vehicle]()
Red ATF streaks on the front of my fuel tank were my clue that the seals were gone.
Before releasing the compression on the main springs by unscrewing the stanchion top cap nuts, I used a 7/32 hex bit in my battery powered drill set on torque-ratchet and spun the damper tube cap screws free. Then I pulled the fork legs off.
Opening up the fork legs revealed that a non-mechanical person had installed new seals at one point. The aluminum had pry bar marks, probably a screwdriver, and the seals seem to have been installed with red Loctite and they were a chore to get out of there without causing further damage.
The mouth of the seal bore hadn’t been chamfered or deburred from the factory, so I fixed that.
Damage that the previous owner had done was superficial and cleaned up okay with a file and sandpaper.
Inside the fork leg was an eighth inch of mud at the bottom, so I made a giant Q-Tip with a wooden dowel and some paper towels and got everything clean and washed out.
Next, the stanchion top cap nuts are removed, and the main springs withdrawn. Measuring the springs revealed they were to original spec length.
The only box end wrench I didn’t have in my tool kit was the 1 ¼” for the aluminum stanchion bottom end plug so I bought one.
Using an open-end wrench here would be disastrous as the aluminum deformed somewhat even with a box end wrench as I removed the plugs.
Again, somebody with a hard-on for red Loctite really went to town and coated it heavily.
When the bottom plugs come out, the whole damper assembly comes out. I very carefully cleaned up the threads on the bottom plug and inside the stanchion, and everybody got a good bath.
Inside the stanchion tubes was rusty so I used an extended flap tool with my pneumatic grinder to clean them up and then passed a kerosene-soaked towel through with a wooden dowel to be sure they were immaculate inside.
I had already bought new seals and O-rings before I found out that there are high-end aftermarket components that can be used here to avail a more responsive action. I’d appreciate advice pertaining to this for future reference.
When I measured over the new damper valve O-ring as installed it seemed to be only about .001” greater diameter than the inside of the stanchion but indeed there is some stiction as is evidenced when raising the bike with a jack, the suspension extends in little stages instead of linearly.
After a thorough cleaning, I reinstalled the damper assemblies. Minimal red Loctite was used around a couple of threads on the bottom stanchion plug.
Next, instead of using the stock wipers, I slid on the new Commando gaiters from Andover Norton.
A dab of grease was used to hold the sealing washers on the end of the damper tubes and the fork legs slid on and the bottom socket head cap screws started.
I made up this whiz-bang special screwdriver from 22” of half-inch round steel stock and a hacksaw and file when I did the forks on my 72 Daytona, and it works here as well to hold the damper tube from turning while torquing the bottom cap screws.
The drain plugs were then re-installed in the fork legs and the main springs were dropped in the stanchion tubes.
The spec for my bike reads 190cc of ATF but I used equal parts of 5 and 10 weight fork oil to achieve 7.5 weight.
Readily available fork oil for me was the Maxima brand.
The bottom diameter of the gaiter rubber is about a half inch smaller than the fork leg upper diameter, but with a heat gun applied (or even a hair dryer I would suspect), it becomes very stretchy and is easily slid down and over.
I found some stainless-steel zip ties at the hardware store that I think look nice next to the polished aluminum legs.
For the top I used black plastic zip ties, and you can barely notice they’re there.
After a quick trip around my local dirt roads the gaiters were indeed covered with road dust along the front so I’m glad I went for this upgrade.
Now that I’ve ridden about 600 miles of combined dirt and highway, they’re caked pretty good and need a wash, but my front suspension seems very nice.
Being I ride a lot of dirt and bumpy roads; I’m half tempted to try going down to 5 weight fork oil and see how it feels.
Joined
·
11,929 Posts
Hi,
97-4003P Damper O-rings replacement. Regrettably not stocked by any retailer except L.P. Williams in GB.
Hth.
Regards,
97-7010 Leak Proof seals and interference-fit steel retaining washers. The washers are easy to fit in the stanchion tops - washers in the freezer for thirty minutes or so, some heat on the top of the slider. Once fitted, in the unlikely event the seals ever need replacing, old ones can by pulled out through the stanchion holes in the washers, new Leak Proofs on their own are available under a different part number.
97-4003P Damper O-rings replacement. Regrettably not stocked by any retailer except L.P. Williams in GB.
Fwiw, I've never put any sort of fastening around any of the Commando gaiters on my bikes, never had one come off.
Hth.
Regards,
Joined
·
440 Posts
So, I guess that’s it.
I thoroughly enjoyed the process of breathing life back into this old girl and she is a sweetheart.
I’m slow and meticulous so it probably took me a couple hundred hours and maybe $3000 in parts.
I replaced every 50-year-old piece of rubber I came across right down to the grommets on the idiot bulbs on the headlamp shell.
The value of the bike on the market is probably less than what I’ve got into it even with my free labor, but I was never looking to sell it.
My wife tells me the local farm museum is looking for volunteer mechanics and that sounds very enticing.
Nothing I did to the bike could not be put back like it was in original condition and I’ve got the parts binned and catalogued.
If somebody wants to make a museum piece out of it after I’m gone, it’s all there.
But in my opinion every change I made from stock, was a change for the better and those are listed below.
Electronic ignition
Electronic Regulator-Rectifier
Pancake Air Filter and hence Retro Side Covers
Fork Gaiters
Current mileage is 5896 and even with her patina I’m calling her better than new.
She runs really well, pulls hard, gearbox is maybe the best I've ever shifted, handles like a dream, no excessive vibration
In honor of Lucinda Williams' album "Ghosts of Highway 20" which I listened to a LOT during the process -
Her name is Lucinda
,
![Land vehicle Wheel Plant Tire Sky]()
I thoroughly enjoyed the process of breathing life back into this old girl and she is a sweetheart.
I’m slow and meticulous so it probably took me a couple hundred hours and maybe $3000 in parts.
I replaced every 50-year-old piece of rubber I came across right down to the grommets on the idiot bulbs on the headlamp shell.
The value of the bike on the market is probably less than what I’ve got into it even with my free labor, but I was never looking to sell it.
My wife tells me the local farm museum is looking for volunteer mechanics and that sounds very enticing.
Nothing I did to the bike could not be put back like it was in original condition and I’ve got the parts binned and catalogued.
If somebody wants to make a museum piece out of it after I’m gone, it’s all there.
But in my opinion every change I made from stock, was a change for the better and those are listed below.
Electronic ignition
Electronic Regulator-Rectifier
Pancake Air Filter and hence Retro Side Covers
Fork Gaiters
Current mileage is 5896 and even with her patina I’m calling her better than new.
She runs really well, pulls hard, gearbox is maybe the best I've ever shifted, handles like a dream, no excessive vibration
In honor of Lucinda Williams' album "Ghosts of Highway 20" which I listened to a LOT during the process -
Her name is Lucinda
,
61 - 80 of 92 Posts
