Kickstart not engaging

[voicey]

Evening folks, this is a weird one but I bet someone here has seen this before....

My GP kickstart won't engage with the starter teeth 90 percent of the time I kick it over, it almost catches but crunches to the bottom of the floor without engaging. Eventually after nursing it slowly, it will take a hold and I can kick it. Sometimes it engages ok. I initially replaced the kickstart plunger after ensuring the starter teeth were ok on the gearbox, same results. I then replaced the kickstart shaft complete with another new plunger, same results. Today I stripped it again and removed the complete gearbox, assuming I'd see something glaringly obvious with a bearing etc. Absolutely nothing to see, apart from some play in the rear hub bearing. I'm almost tempted to buy a new gearbox and replace every bearing, shim etc but the thought of the problem still being there once rebuilt is stopping me. Has anyone seen this before?

[dapper]

Check the reference pin on the kickstarter shaft. The constant wear from the ramp can cause a deep groove in the pin preventing the plunger from coming out far enough to engage with first gear.

[voicey]

Hello mate, those items have all been changed already. It's a total puzzler. So far it's had a new chain case (I wanted a new one anyway so it seemed like the right time), shaft, plunger (2 of) and pins (2 of). I bought the scoot with this problem and despite changing all of the mentioned parts the problem remains. It's in bits as I speak, I'm just going to have to replace the gearbox and every bearing then shim it all up and see how it goes. I'm wondering if I have a rogue part fitted somewhere.

[holty]

a good mod on the gp is to cut the ramp off the backplate and add an li type ramp to your side case, it just needs drilling and tapping, it might make it easier to get it to work right, maybe the plunger spring is too short, or the slot it runs in, just buying a new shaft dosnt mean the new shaft is correct, heard a few stories about duff kickstart shafts

[voicey]

I'll check it out Holty, cheers. The shaft I bought is a Casa one, but I'll have another look at it and see if there's anything obvious.

[holty]

i would expect that to be good, check plunger and spring next, did you check endfloat on your gearbox ?

[dazblakey]

Just had the same problem had to take 3mm off the shaft as it was catching the gear teeth slightly burring and keeping the kickstart plunger in after the removal of 3mm worked fine

sent from over there next to the tree

[dazblakey]

The old gaskets used to be thicker new modern ones are like paper thin compared to the cork

sent from over there next to the tree

[voicey]

Holty, good point regarding end float. I noticed there was a 2.6mm cyclone shim fitted and there was still far too much play. I'm pretty sure 2.6mm is the biggest available (I actually thought 2.5 was the max). I'll check the items suggested by Daz Blakey too, but the whole thing is a bloody pest. With everything I've changed so far the problem must lie deeper than the shaft etc, as those items have all been changed (some of them more than once).

[bazza3004]

I had to make the pin slot 2 or 3 mm longer on a mates as it was doing same thing