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Discussion Starter #1 (Edited)
This is on a 1973 T140. The primary chain was making some noise, so I took a look at the adjuster, and the adjuster rod threads were completely worn away so the adjuster nut was presumably slipping back under pressure, I ordered a new rod and nut, firstly the new nut (the tube like adjuster) was slightly bigger diameter and wouldn't fit in the crankcase hole, so I turned it down a little on the lathe. Next as I tightened up the new adjuster it gets to about half way down the threaded part and sticks... The new rod now has damaged threads aswell! I eventually broke the rod by forcing the adjuster nut!

Has anyone else experienced this? I think maybe the small cylinder with a hole through (goes into the adjuster blade) it is damaging the threads, it also looks to have an oval shaped hole through it so maybe I should replace this aswell?

The other question I am asking myself is whether the chain itself is too loose and worn and the adjuster is having too much pressure put on it and therefore damaging the threads... Ho bent should the adjuster blade get to adjust the chain correctly, mine is quite bent I need to take a photo? When can you tell if the primary chain is passed useful life?

Thanks for any help.
DaveG
 

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If the tensioner blade is very arched, the chain would benefit replacement. I have had adjuster rods snap due to this ached blade. It would seem your supplier is supplying very cheap parts of dubious quality. It might pay to ask for Harris parts which are likely better than most. A Renolds chain is lasting a very long time on my bike at the moment. A previous cheaper one lasted just 4000 miles.
 

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Mine has all the arch in it that the mechanism will allow in order to have the proper slack. I should replace the chain but it’s still in spec. I had occasion to remove the mechanism and re- install it and had no problem with its operation in either direction. The only problem I’ve ever had was replacing a worn adjuster, that’s just normal wear and tear. You need to just take it out and find out what’s going wrong.
 

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I think your primary chain is stretched and needs replacing.
The picture shows the chain/adjuster prior to being adjusted.
As it is difficult to get a screwdriver into the hole for adjustment, I ground a suitable bolt, (shown).
 

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I think your primary chain is stretched and needs replacing.
I agree, this is a pic of my 500 with the slipper not tensioned but it only takes a couple of adjuster turns for the chain to have the correct amount of slack, 1/2 inch in my case.
 

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Hi DaveG, Triumph posted primary chain measuring & wear limit in shop manual. I've always gone by that. At 3/29/18, 23514 miles my chain was less than 1/2 worn compared to wear limit. But you have to remove chain to measure. I compared to new Renold chain at Rabers when I had it apart to work on clutch & reseal rear sprocket. Hmm... New chain has pin play also & my chain had hardly more stretch than the new one. I worked the new chain back & forth to squeeze as much grease from pins as I could. So I reinstalled the old chain which is from new.

Factory says make 2 marks 12" apart. That's 32 links. Max stretch is 1/4". I got 3/32 on my chain. The new chain was just a whisker under 2/32".

I pushed chain together & made 2 marks 32 links apart. Then stretched chain hard & made a 3rd mark. The last 2 marks were 3/32" apart.
So where does that leave me? I'll call it less than 1/2 worn.

I find the adjuster screw tends to tension chain about 1/8 tighter for every 1/2 turn once you get close to the proper tension. What is proper tension? I have owners manual & workshop manual from new the day I purchased bike. One says 3/8", the other 1/2".

The chain has only been adjusted 3 times now. Once at about 1000 miles when it rubbed the tube & wire & case. Once at about 12000 miles when I did cush hub rubbers & just recently at 30500 miles a few weeks ago. After the first adjustment at 1000 miles it only took 1/2 turn at each adjustment. I very carefully find the tightest spot when adjusting. Then pull clutch lever & spin pressure plate & retest to see if tension changes. It doesn't seem too. I then find loosest spot & pull chain up hard as I can to make sure it doesn't rub wire tube.

For whatever reason I see many 3 row chain bikes with chain wear marks under clutch basket sprocket area. Also on the alternator wire tube.

I tend to set tension just a whisker under 1/2" measured with a 1/2" wood dowel I put 1/8" apart marks on. I put dowel though primary filler hole. I push down firmly on dowel & push chain up firmly. On my photos my alternator wire tube looks different than original. I fabricated a longer thinner one to keep chain from rubbing as easy, but more importantly it makes it almost impossible for wire to droop when hot & rub chain. I've seen several 3 row chains where chain was rubbing wire.

Regarding your adjuster bolt damaging the threads I ran into that exact thing a year ago on a new repro one. Compared to the original Triumph one the threads didn't go down far enough. It was not too fat though. When threads bottomed out still would need at least 4 1/2 turns to take tension. This used chain measured very close to 3/32" as well. Did not replace chain. The seller exchanged adjuster bolt for a perfect condition used original Triumph. I worked good. Used a new rod & it worked good with the original version bolt. Reused the tension blade as it was perfect.

I find once you get to the proper tension an extra 1/2 of adjuster will feel like something is binding. The chain will feel drum tight when adjuster passes high spot on its cam. Now chain is too tight. It can be hard to back off. If you force it something will break. You need to kick motor over until you find loosest part of chain & pull clutch lever which seems to give a trace more play & it will usually back off without damage.

I really don't know what the 12" means because I can compress chain & it's less than 12".

I don't know how to measure chain on bike. I suppose you could use a large Vernier caliper.

Here is some photos of my '73 Tiger at 12k miles. One some you may notice a 1/4" aluminum tube reaching bottom behind chain. That is the tube I use to siphon primary oil as it takes about all night to drain & the siphon removes a little more oil.

Maybe you could look at the end of the blade compared to the screw holes on case & make a calculation to what you have. I don't know how well my photos actually replicate the arc. To be clear this chain has correct tension in the photos.
Don
 

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Discussion Starter #10
Clutch basket moves about

Hi Thanks for all the replies, I decided to remove the chain and get some measurements to see if a new chain is required, and both the rotor (magnet) and the clutch basket seem to have a fair bit of side to side movement in them with no tension on the chain - is this normal? The whole clutch basket seems to move 8-9 mm from side to side, I don't think this can be right - and would account for the noise I am hearing, as it only makes a noise when in gear and moving, there is no discernible noise from the left side with the bike in neutral.

Is there anyway to remove the clutch basket without the factory puller? I have one for jap bikes but I assume that this one would be some weird thread?

I am less concerned with the rotor as the engine gears are solid, although I need to check with the thing torqued up correctly.
 

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much easier with the puller, and its only a tensioner...tension it up then firm tap with a hammer on the tensioner bolt. If you try to use it like a normal puller you will strip the threads.
 

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Discussion Starter #12
Well I removed the clutch and couldn't spot any wear on the chain, I removed the chain (you don't have to remove the crank gear to do this, but you do have to remove the 2 long studs at the front. The chain measured out at 84 links and a total length of 31.5" which gives a pitch of 3/8" which is like new so there is no wear or stretching (that doesn't mean it is the right chain!).

The rollers all fell out when I removed the basket but again nothing to report apart from some wear on the basket grooves, so everything was cleaned and reassembled I just need to wait for delivery of my new tension rod and nut.

I should mention that having done this there is no longer any play on the clutch basket! Maybe I did fix something!
 

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Well I removed the clutch and couldn't spot any wear on the chain, I removed the chain (you don't have to remove the crank gear to do this, but you do have to remove the 2 long studs at the front. The chain measured out at 84 links and a total length of 31.5" which gives a pitch of 3/8" which is like new so there is no wear or stretching (that doesn't mean it is the right chain!).

The rollers all fell out when I removed the basket but again nothing to report apart from some wear on the basket grooves, so everything was cleaned and reassembled I just need to wait for delivery of my new tension rod and nut.

I should mention that having done this there is no longer any play on the clutch basket! Maybe I did fix something!
So, you did not measure the amount of chain wear as described earlier.
"When the chain is compressed to its minimum free length the marks (12" apart) should coincide with the centres of two pivot pins 32 links apart. When the chain is stretched to its maximum free length the extension should not exceed 1/4"."

The sprocket alignment should also be checked with a straight edge, shims can be inserted under the engine sprocket for alignment.
If its out of alignment, this could be the clunk heard.
 

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Hi Dave,

rotor (magnet)
seem to have a fair bit of side to side movement
less concerned with the rotor as the engine gears are solid,
As this has gone more than 24 hours without being questioned ...

:confused: What are "engine gears"? Primary sprocket on the crankshaft?

Then what do you mean by "side to side movement" of the rotor - along the crankshaft or forwards/backwards and up/down relative to crankshaft or crankcase?

You should very definitely be more concerned about any independent movement in the rotor - there is (should be) only eight-to-twelve thou. between rotor OD and stator ID so there can't be much of that "movement" before spinning rotor starts to rub on not-spinning stator, with disastrous consequences for both and surrounding components. :bluduh

If forwards/backwards and up/down is actually the crankshaft, that's a knackered main bearing. :(

Otoh, if forwards/backwards and up/down is between rotor centre and outer, that's a knackered rotor. :( Rotors are a hexagonal steel centre, six magnets sitting one on each hex. face and the whole lot held together by non-magnetic metal cast around and between magnets and centre. Regrettably, that non-magnetic metal casting does come loose from the centre, acceleration and deceleration of the engine then causes relative movement between centre and outer, the centre forces the magnets outwards ... 'til they rub on the stator ... :Darn

"side to side movement" along the crankshaft might be just a poorly-tightened rotor securing nut and/or failure by a DPO to fit a tab washer/properly, but it's wise to check for the aforementioned movement between rotor centre and outer.

Talking of rotor securing, later twins dispensed with the tab washer and used a special "Fan disc" lock washer (21-7024) between rotor and nut; people that should know have posted here and in the BritBike forum that the later washer works better.

1973 T140.
If you post this and a basic Location in your Forum User Profile, they'll appear automatically beside all your posts - helps others when the advice you need is model-, version- and/or location-specific.

Hth.

Regards,
 

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Hi DaveG, Interesting way you removed the chain & clutch. More common is pulling clutch & crank sprocket together. I use automotive vibration damper puller for crank sprocket.

Since you have grooving on hub & basket, you've got some miles on the clutch parts. I've noticed when cush hub rubbers deteriorate I can hear an odd clack from motor. Can sound like from piston/head area to my ears sometimes, other times lower. Riding in canyons as bike crests a sharp hill it can clack when rolling throttle back on. Sometimes can be heard as standstill blipping throttle also. The rubbers tend to have a short life span these days. Only some times 3-4 years & 6-10000 miles. I've only used the black rubber type rubbers.

Since the basket is off I'd recommend replacing the rubbers. As you now see there are 3 hex bolt heads on back side of cush hub. The front side from factory will look rather like screw driver slots. These slots are the result of the swaging done at factory to secure bolts. 100% of the swaging MUST be ground off, or the threads will be damaged in the outer cover of cush hub. The 3 bolt will then need to be replaced. You'll need to make special tools to hold hub in vise & counter turn the drum to compress rubbers to install them. Workshop manual speaks of using a tyre iron to install rubbers. I've never been able to do that. Do a search & I posted photos of how I did that.

Grooving of the hub/basket is bad for clutch operation. Minor grooving can be filed out. Deep grooving can be filed also, but the slots get wider & it will effect operation as well. Just doesn't release as good as it would from new. Wear on the spider sides, side plates & bores of plates, end of spider will effect operation as it can allow the hub to cant in relation with the basket effecting plate contact.

Regarding basket play the clearance of the thrust washer when good is about .017". You really need to use 3 feeler gauges around the washer at same time to measure accurately. Triumph give no spec, but I find if washer is worn it can cause drag when released. I always replace the washer. Basket doesn't wear much where thurst washer rides, but the face of the tapered hub can wear. The washer tends to wear fairly quickly, so I always renew it when basket is off.

When you say play of basket, are you actually speaking of wobble, meaning wiggling in/out. That is normal & is a lot even with all new parts. If you didn't know better you'd be sure something is wrong. When the thrust washer is worn, it will wobble way more. Triumph gave no spec for wobble either. Grabbing the main shaft itself pull/pushing straight in/out you should feel basically no play. If it moves noticeably it's often because the nut on the right end of shaft has backed off.

I most strongly recommend using blue loctice 273 or 272 on both clutch & alternator nuts. 273 is a little more oil resistant, but 272 works fine. It will remove fine without heat later. Look close at lock tab for alternator nut where it engages keyway. Bend tab as needed so it actually enters keyway. Sometimes it does not so it doesn't lock.

DO NOT guess on torques. It is very important to have both these correct. If you don't have torque wrench, buy one. Wipe oil off taper of shaft & hub with dry cloth before installing.

Here is photo of my worn clutch grooves. This amount of wear can be felt in real life as clutch drag & will tend to cause slippage sometimes also. I filed them. Much better, but not good as new.
Don
 

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I know it's not the rotor, but whilst changing the primary chain and sprocket on my last T140D I noticed some back and forth movement on the front sprocket. Hoping against hope that it was the sprocket splines, but no such luck



 

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Hi Jimmymc, Thanks for posting the photos. That's too bad.

Photos show why it's so important to do things correctly, use torque wrench, verify lock tab, why I use Loctite as well.

Another thing is verify the threaded stud is the correct way round in crank shaft. If stud is backwards you can run out of threads, so nut will look tight & take torque, but in fact the rotor & sprocket will not be pinched tight to crank.
Don
 

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Cheers Don, glad to help ;(

This was a few years ago, so I'm over it. This was discovered the first time I had pulled the primary apart so I claim alibi. Funnily enough the bike still ran right up to the point I pulled the sprocket

I sold the bike as was, and bought myself my wee 500, which I have subsequently sold and bought my ultimate bike, which I have lusted after since I was 18 and buying my 1st Triumph

So keeping it on topic, it will be fun when I need to replace this primary chain

 

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Hi jimmymc, Nice bike!! I've always liked Tridents, especially the sloper motors.

Dick Mann raced them at Laguna Seca raceway, showroom stock production. Only change allowed was tires. They still had blinkers & everything. He won the series. We all would ride our Triumphs down to watch.

There are several Tridents in our club. Impossible to keep up with on our twins. They are runners!

The electric start is a real bonus. They guys that have them, it seems to work good.

There are a few real experts on triples in the club & set the primary to perfect alignment & set up the clutch perfectly.

Someday I might get one. Oddly they are not that costly in my area. Finding a good one might be hard though. A lot of them are kind of beat up & need lots of work. The really nice ones the owners love them & there's a line for when the owners pass.
Don
 

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Discussion Starter #20
Noise still there

OK guys thanks for your responses, some less on topic than others! I rebuilt the clutch as was and there was a lot less play on the basket - good.
I purchased a new rod for the tensioner and managed to tension the chain correctly the bend in the tension blade is significant! I wonder if someone has installed a chain with too many links (84) how does one calculate theoretical chain length, maybe I should try an 83 or even 82 link chain?
The bike starts easily and in neutral zero noise, when I pull the clutch and engage first gear - zero noise, as soon as I am rolling there is a whirring noise from the primary chain case - I am pretty sure it is not further back i.e. not wheel or secondary chain related.

I need some kind of action plan to fix this as I am stumped, without just replacing everything in there, can I run the bike a couple of minutes without the primary cover in place - may be able to see something happening?

Any additional help out there?

Thanks in advance.
 
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