Hi, big end went on my old 950cc Cali3, so bought a replacement T5 850cc engine, shipped from Italy.
Problem: Gearbox fits into Flywheel, and clutch (deep spline), we changed the plate from the clutch pushrod to the old one, Slight variance between the two plates. Tested gear engagement, pushrod and clutch all appear fine, put the engine back in frame, attach the Universal Joint/ Shaft onto the gearbox splines, again all appears good. Back wheel engaged on rotation. When we tighten everything up, fit the gear pedal, set the clutch, pushrod and all appear good. However, when the bike is taken off the jacks, and we engage any gear, pushing the bike forward manually, the flywheel doesn’t turn, the back wheel is free, gearbox appear to be attempting to engage, just nothing?? This has happened on 3 rebuilds on this set up?
Any ideas would be much appreciated.
The engine fires and sounds good? - A real head scratcher…
Method to strip frame is crabbing, and removal of rear wheel and shaft…
Assuming you have used the old gearbox and not done anything to it then I am thinking the problem is with the clutch. Is there free play on the clutch arm on the back of the gearbox? It could be pushing on the push rod.
Is the thrust piece which the pushrod pushes on, in the centre of the pressure plate, located properly, it is keyed into the plate, if not fitted correctly it sits proud and so fouls the end of the gearbox shaft and lifts the pressure plate so clutch is prevented from engaging fully and just slips, guess how I know.
I’m guessing you’ve had similar! So pretty sure it’s in, checked with clutch arm detached and manually clicking through gears whilst turning rear wheel. All engage! So, going to loosen off the arm tension, re set clutch completely and set up gear shift, if that doesn’t work then, I’ll follow your idea! There are 2 different rod lengths available, which I wasn’t aware of, we changed the plate you referred to, with the plate from the 950 which were originally married, so hoping this will resolve!
You may have to take the thrust piece right out again to be sure, just looking at it in situ it still looks right, thing is the hole it goes in is not completely round, has 2 flats, and corresponding shoulders on the thrust piece. Had me going round in circles, I figured somehow it was as though it was too thick but I couldn’t see how. Soon as I took it out the penny dropped.
News in!!! So, decided to check the plates, bearing in mind the T5 engine has 12.5k miles on it and the clutch should have been fine, on inspection they were knackered!
Swapped the 950 plates into the T5 and hey presto! Out for a run! Now tweaking and setting up, may be posting regarding needle and jet settings? Being as the carbs are delortto air and we’re set for the 950 engine, they may need further adjusting?