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Discussion Starter · #1 ·
Hi all,I'm new to this site so first I had better introduce myself ,my name is Bill originally from England,now living in the Charente s w France.Yesterday I took delivery of a 72 tr6r,it has been restored several years ago engine fully rebuilt restoved frame etc this was in 94,Ive got the reciept for the engine rebuild,then the guy who went to all this expense must have lost interest coz its only done 130 miles since,Ive got the old mot certs.Obviously I need to run in the engine,but how long for and at what rpm,this is where the problem lies,the bike starts first kick every time its got a boyer ignition and idles sweetly at just over 1000 rpm but on the road it wont rev over 4000rpm if I open the throttle at this engine speed the motor dies as if I had closed the throttle,can't get my head round this one,any help greatly appreciated,
Great site,
regards,
Bill.
 

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Welcome.

Quite likely you are closing the enricher "choke" slide, instead of opening it. To open it, you must draw up the cable completely with the lever.

If this isn't the problem, you may have totally blocked air filters, or your timing is set incorrectly. Could be other issues, byut these are the most likely.

You'll need to strobe time the ignition to get it right.
 

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Discussion Starter · #3 ·
Welcome.

Quite likely you are closing the enricher "choke" slide, instead of opening it. To open it, you must draw up the cable completely with the lever.

If this isn't the problem, you may have totally blocked air filters, or your timing is set incorrectly. Could be other issues, byut these are the most likely.

You'll need to strobe time the ignition to get it right.
Thanks for the promt reply,the ignition was strobed when the engine was comisioned after the rebuild, not been touched since,am I correct in thinking the choke is in the off position when the lever is under tension? I tried riding the bike with the air filter removed this made no difference .I took it out for a short ride today, 7k checked the colour of both spark plugs afterwards they were the normal sandy colour,there is no popping back on the over run it just won't rev ,above 4000 ish,
Bill.
 

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Did you replace the spark plug wires? If so did you use resistive wires? If not the Boyer will die like that at high RPM. Too much noise. Unless it is the analog Boyer. Just a thought.

TangoMike
 

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Discussion Starter · #5 ·
Hi all,I'm new to this site so first I had better introduce myself ,my name is Bill originally from England,now living in the Charente s w France.Yesterday I took delivery of a 72 tr6r,it has been restored several years ago engine fully rebuilt restoved frame etc this was in 94,Ive got the reciept for the engine rebuild,then the guy who went to all this expense must have lost interest coz its only done 130 miles since,Ive got the old mot certs.Obviously I need to run in the engine,but how long for and at what rpm,this is where the problem lies,the bike starts first kick every time its got a boyer ignition and idles sweetly at just over 1000 rpm but on the road it wont rev over 4000rpm if I open the throttle at this engine speed the motor dies as if I had closed the throttle,can't get my head round this one,any help greatly appreciated,
Great site,
regards,
Bill.
Hi finally got to the bottom of the problem,my mate in England traced the chap who had the engine rebuilt he said it had been set up so it couldn't be over revved during the run in period,I had a look under the points cover and found the boyer had been set fully retarded,Ive advanced it about half way its a lot better now,got a strobe light on order will be here next week ,Ive never used one on a boyer before what is the best way to do this,
thanks,
Bill
 

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Pull the bike out on to an open driveway and set up a large fan pointing at the front of the engine. Park a car close to the work area, so that you can connect the timing light's power leads to the battery.

Clip the inductive pick-up to the spark plug wire, remove the timing window on the primary cover, remove the ignition trigger cap and slightly loosen the two pillar bolts so you can adjust the stator plate. DO NOT press on the two small coils to rotate the plate, but instead use a small screwdriver pressed against the edge of the screw slot at the top of the stator plate (tap the screwdriver with another screwdriver's handle if need be).

Inviting two friends over to assist will make the job easier, one to start the bike and rev it, one to hold the timing light pointed at the rotor mark, and one to adjust the stator plate's position.

Rev the bike up to 5,000 RPM and set the timing on the mark of the rotor. It sounds like death, but that's how it's done.
 

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Discussion Starter · #7 ·
Pull the bike out on to an open driveway and set up a large fan pointing at the front of the engine. Park a car close to the work area, so that you can connect the timing light's power leads to the battery.

Clip the inductive pick-up to the spark plug wire, remove the timing window on the primary cover, remove the ignition trigger cap and slightly loosen the two pillar bolts so you can adjust the stator plate. DO NOT press on the two small coils to rotate the plate, but instead use a small screwdriver pressed against the edge of the screw slot at the top of the stator plate (tap the screwdriver with another screwdriver's handle if need be).

Inviting two friends over to assist will make the job easier, one to start the bike and rev it, one to hold the timing light pointed at the rotor mark, and one to adjust the stator plate's position.

Rev the bike up to 5,000 RPM and set the timing on the mark of the rotor. It sounds like death, but that's how it's done.
Thanks for that seems pretty straight forwards,there are two timing marks on the rotor is this normal?
Bill.
 

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Discussion Starter · #8 ·
Thanks for that seems pretty straight forwards,there are two timing marks on the rotor is this normal?
Bill.
Hi again ,Ive now tried all of the above nothing has changed,the spark plug leads look new but I dont know if they are the correct ones.they are bougicord 403 classic,it also reads "autoradio" on them,possibly they should be on a car? any idea's guys?I was on the phone to Norman Hydes in England yesterday they have not a clue as to what this problem is and nor do I ,I should add that when I strobed the timing the bike revved to 5000rpm no problem but when on the road it cuts out around 4000rpm,when I roll the throttle back it picks up again,I'm completly baffled.
regards,
Bill.
 

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Hi again ,Ive now tried all of the above nothing has changed,the spark plug leads look new but I dont know if they are the correct ones.they are bougicord 403 classic,it also reads "autoradio" on them,possibly they should be on a car?
regards,
Bill.
Bill,

"autoradio" wires are a suppressor wire. They are used to keep
the buzz out of the radio in a car. As I remember the cables used
in earlier Triumphs was a copper core. But I would need someone
with an old machine to chime in on that and if with the copper
core wire suppression caps are used.

Pookybear
 

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Should be copper core (wire). Autoradio sounds like carbon core which are not suitable for screw-in plug caps. Changing them will at least eliminate one possibility.
 

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I don't know diddly, for starters, but it seems as if the ignition is good for 5000 rpm in the driveway, but not on the road. That means the engine is either running out of gas or running out of spark under load. Since it doesn't seem too rich, from your spark plug readings, you might check your fuel system, starting from the tank thru the main jets. The description of the engine picking up again once you throttle back seems to say it is starving for fuel.
 

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Oops, sorry, you didn't give plug reads, must have been another thread. But check your plugs after a road run, it might tell you what's going on. Good luck, I'm sure you will sort out the difficulty.
 

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Discussion Starter · #16 ·
Sorry Jimi I meant volts. Boyer needs juice. Won't run right without it.
Hi, thanks all,I thought I had this sorted When I discovered the main petcock was completely blocked and the reserve partially blocked,I went through the whole fuel system cleaned everything from the tank to the carb,there was a lot of crap, but this has made no difference,the guy who built the engine was contacted and he said its definately fuel and suggested going up one size on the main jet when I rang Norman Hyde to order one they said "we will be very supprised if this is the problem" but did mention the plug leads so I will order some next week,the battery is ok,I think, my multimeter is playing up,but I have the battery on a optimate which is showing good condition and full charge.Thanks for all your comments they are all greatly appreciated.
Regards,
Bill.
 
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