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[Wheaters]

Took the outer cover off the gearbox today. It soon became clear that the fault lay somewhere with the return spring. Everything appeared to be correctly fitted. However, after I fiddled about with it (basically, just pushed it around and relocated the “legs” using a screwdriver, it suddenly began to work as it should. I fitted it all back together, using a new gasket and refilled it with oil. A quick test ride up and down our cul-de-sac confirmed it worked nicely on all down changes. I’m hoping this is a permanent fix but it was too cold to ride any longer.

[Wheaters]

The bike is now just about as I intend it to remain ( = I can't afford to spend more time and money on it).

(That's Andy A's bike behind it).

[Wheaters]

The new return spring in the 5 speed gearbox didn't cure the fault of the selector lever not readily resetting to allow the next down change. I got annoyed at a few too many embarrassing moments after having to stop at junctions and trying to pull away in third, which doesn't work very well on a 350!

It was almost as if the weight of the gear lever itself was just slightly too much for the return spring to reset but the slightest touch upwards by hand would reset it so the next lower gear could be found by pressing down. But doing this on the bike sometimes resulted in an upwards gear change, the opposite of what I was trying to achieve! I decided to think around the problem. I couldn't see how a stronger return spring could be fitted inside the box, so I decided to design and fit one on the outside!

I've since fitted two identical springs, one inside the other. The only "permanent" thing needed was to drill and tap a hole in the selector lever. Everything else can be removed in a couple of minutes. Job done, the springs reset the lever so the gearbox now works perfectly. I've since protected the springs by fitting a piece of soft plastic tubing over them. My boot doesn't touch them as they are tucked back inside the gap between the two casings.

An added bonus is that the thread in the exposed gear shaft in the casing is protected from road dirt; I fitted a matching screw and washer on the other end at the rear of the gearbox for that reason.

[rattonshaw]

If you can find a way of lengthening the pull on the clutch, it makes a world of difference.

I've got a GPZ500 clutch lever on the 612 bullet and that's what's made the difference. No hint of crabbing at any point, even with prolonged use. It does slip but not because of the release action, I think that's bhp related. It has a way longer pull than the standard clutch because the pivot point is further away from the bars (and is span adjustable). It also bolts straight on using the standard cable.

Do you happen to know if the GPZ500 clutch lever assembly on your pre-unit bike will fit the later UCE engines, specifically a 2014 Electra? I've compared clutch mechanisms for various model years on Hitchcocks parts catalogue and come to no conclusion. Also, what model year does your GPZ500 clutch lever assembly come from; there's probably differences in different years.

[stinkwheel]

Do you happen to know if the GPZ500 clutch lever assembly on your pre-unit bike will fit the later UCE engines, specifically a 2014 Electra? I've compared clutch mechanisms for various model years on Hitchcocks parts catalogue and come to no conclusion. Also, what model year does your GPZ500 clutch lever assembly come from; there's probably differences in different years.

I don't think there's much difference in the clutch levers between the electras and pre-unit ones, never tried one though so you'd need to suck it and see. The clutch I'm using is a post '94 one which is span adjustable, The pre '94 ones have exactly the same fitment but aren't span adjustable. Got one on my trials bike too. In fact, I also use one flipped upside down as a brake lever.

[Daiwiskers]

If it's any help I have fitted a clutch lever and clamp from a GPZ 600 I think it is from the early 2000's
But again this is on a pre unitv

[rattonshaw]

Thanks for the info on the clutch lever assembly. I'll try and get hold of one or the other. The bike has that problem of difficulty selecting neutral at a standstill with the engine running. Clutch play is set to a bare minimum and I'm not prepared to take the clutch apart and check the plates just yet, especially with only 3,000 miles on it and no signs of abuse.

[stinkwheel]

Your difficulty finding neutral may be more of a gearbox design issue than a clutch adjustment one. It's not always straightforwards to get neutral at a standstill on my 612 and it has one of Bob Newbys superb clutches fitted (which works better than the clutch on my Honda). I usually deal with this issue by going into second then using the neutral selector lever.

[Daiwiskers]

Not trying to teach anyone how to suck eggs but I always try to find neutral while still rolling
A trick I learned back in the late 60's early 70's 3 speed Bantam boxes could prove problematic when abused (thinking about it the whole bike could be problematic)

[rattonshaw]

Selecting neutral while still rolling is not always possible in crawling traffic or queuing for a trials section and the UCE engine doesn't have a neutral selector lever. As for sucking eggs; the older I get, the more frequently I forget how to do it