Clutch Stuck - 1977 Triumph Bonneville T140v

The clutches can be a bit sticky after standing. The normal starting procedure includes kicking the bike over with the clutch depressed and the ignition OFF until the clutch frees up (it is really obvious when this happens). Failure to do this can damage the gearbox when you select a gear.

The clutch is located between the kickstart and engine which means that when the clutch is freedom off the engine will not turn over if you depress the kickstart with the lever pulled in.

If you are having clutch issues it is maybe time to adjust it and maybe even service it. Adjustment starts with adjusting the pressure plate run- out (critical but needs primary cover off) before adjusting the pushrod and finally cable free play.

In addition to cable/ pushrod adjustment, routine maintenance includes lubricating the cable and ensuring it has no sharp bends.

Deeper maintenance includes removing primary cover and cleaning plates, checking basket (notched slots, roller bearings, shock absorbers rubbers) and checking spring lengths.

All of this will help minimise clutch stiction.

There are a few mods which can be made to improve the clutch action including a 7 plate conversion (with 650 springs), alloy pressure plate and smoothing out any notches in the basket.

Servicing the clutch actuator in the gearbox cover and the gear index plunger under the gearbox also make a noticeable improvement to clutch/ gear operation.

My TR7RV gearbox has all of the listed work and mods plus a belt primary, gear changes are siky smooth now plus neutral is a dawdle to find.

 

I also have the Aerco kit with T120 springs and this works well. Adding an alloy pressure plate at the same time also helps, these have less flex and make it easier to adjust them to run true. I have an SRM alloy plate which also uses a needle bearing on the clutch pusher.

A point to consider when fitting a 7 plate kit is the diameter of the pressure plate,. The ID of the friction plates is larger than stock plates so make sure whatever pressure plate you use is large enough to overlap the friction plates.

I also found that a couple of often neglected items had a significant effect on the hear change. The index plunger under the gearbox is well placed to become clogged with sludge which can gum it up affecting gear indexing and the clutch pusher mechanism collects muck and grit plus the balls can become crusty affecting clutch operation. Both need the gearbox drained which is a good time to use a quality oil.

The index plunger is easy to dismantle and clean. Once cleaned, check the plunger tip and replace if worn, also fit a new spring if you don't know when it was previously changed. Make sure you use the correct sealing washer as the wrong once affects the plunger preload. Finally prime the plunger assembly before refitting. This all gives a more precise gear change provided the cam plate is in reasonable condition.

The clutch pusher on the inside of the gearbox cover benefits from a good clean, also check the balls and replace if worn or rusty. Oil on re-assembly This all gives a much smoother clutch pull. NOTE check the size of the old balls and replace like for like as different sizes exist.

 

i have found that slathering the clutch plates with white lithium grease before installing them helps them to engage smoothly.

 

@Charles West
Welcome to the family. Do hit the upload a file button bottom right. Let the inmates see the Bonnie. Joe

 

@Charles West
Thanks for the picture. And it is a real nice machine beautiful in fact. Joe

 

Those nuts on the springs shouldn't be screwed all the way home. They should be almost flush with the end of the screws maybe slightly deeper. You will notice they click as you slowly tighten them. That's to stop them slackening off when running. You adjust them so the clutch runs "True" when you pull the clutch lever in and kick it over the springs can be adjusted a bit at a time to get it to spin "True" as in . . . the cover where the springs sit has no wobble when you kick it over. It doesn't matter if one looks tighter than another...because it's compensating for the individual spring strengths. As long as the clutch doesn't slip the springs are tightened down enough.