Engine cuts out when taken out of neutral____ clutch??

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storkfoot
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New build standard TS1. Not been on the road yet. Carb is not set properly yet but it ticks over on the stand without cutting out (PHBH 30 on a 55 pilot) and looks a bit rich beyond that.

The problem is that when I pull in the clutch, and move the lever to engage gear, the engine cuts out, sort of like all the power is immediately being transferred. It doesn't allow me to let the clutch out. It cuts out with a jerk (sort of like when a Vespa engages first gear if you know what I mean). Problem persists if air screw is lean or rich.

Clutch is 4 plate Surflex B with strong MB springs. The basket is a machined one at the bottom so would accept 5 plates if needed. All components are GP except I used the thinner LI top plate. I'm pretty certain the plates separated fine when compressed and I don't think that the top plate looked at risk of flipping out of the top of the bell :idea:

I haven't taken the sidecasing off yet as I want to check the timing with a strobe first this morning.

Is this a clutch issue, and could it be to do with the LI top plate?
bristolmod
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Clutch issue I recon....

did you soak plates overnight?
clutch cable adjusted properly?
if you pull in the clutch and then depress the kick start, is there any resistance?

Chris
Scootering since 1968.
storkfoot
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bristolmod wrote:if you pull in the clutch and then depress the kick start, is there any resistance?
Chris, yes, you're right, it's trying to turn the flywheel and intermittently it is turning. Which points to clutch drag caused by the plates not separating properly?

The cable is set right with just a tiny bit of slack.

Paul
WINTERMODEL150
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Hi,if the clutch is set up correctly ie 1mm clearance between the corks when its fully depressed and the plates have been soaked before fitting then it sounds like the cable needs adjusting,keep adjusting the cable ,you will find this will work i've had this problem a few times on new builds.

Dean
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coaster
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Paul, what happens if you increase the revs a bit when selecting a gear? I have had dragging clutch issues with with the Jet 225 engine since I built it last year caused mostly by the limited stroke of dog legged levers. But, it doesn't cut out when engaging first, just drags a bit :wtf:

As you already mentioned, if it all went together ok and compressed up enough to easily get the circlip in then there shouldn't be a problem :? Maybe try getting the back wheel off the ground and see it is cuts out then?

Thinking lateraly, could it be something completely daft like the clutch/gear cables disturbing/shorting a connection in the headset?
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hungdog
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Had same symptoms on a vespa, 2 new sets of clutch plates all soaked over 24hrs only to find the crank was rubbing on casing causing it to cut out when put in gear. Hope it's not that and just a clutch problem. :roll:
Thats what happens when you take a hammer to the crank to try and get a sheared woodruf key out. :oops:
storkfoot
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I thought I'd cracked it this afternoon.

I took the chaincasing off to find the GP plunger in bits. On closer inspection, I found that the kickstart shaft had been rubbing on the top clutch plate. Also, the top clutch plate was sitting very very close to the top of the basket. Clearly I wasn't having a good day when I put the clutch together in the first place :oops:

Anyway, I dremmeled the kickstart shaft and stripped clutch. On rebuilding it I fitted the thicker GP top plate which has moved the top clutch plate away from the very top of the basket. The plates seemed to separate ok when the compressor was applied.

I fitted the chaincasing back on to check the kickstart shaft wasn't still catching on the top plate. It wasn't. Now I haven't put the oil back in but I still seem to have the same issue with the plates not separating. That's were I've left it till the weekend :(

Can I just ask one more question :roll: The more I look at the plunger, the more I doubt whether I know which way round it is supposed to go :oops: Is this the right way ie. it sits flush and has the cut out bit facing the front of the scoot?

Image
dapper
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Plunger is in correct position. Don't forget that the clutch operating lever should be at right angles to the engine when all back together. You sure your kickstart spring isn't sitting to proud? Have you tried bending up the ears on the bottom cork so it allows the bottom cork to sit a little lower?
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dapper
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Oh, and double check that the clutch springs are all in straight and properly seated.
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WINTERMODEL150
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Hi,i did have a problem with a distorted clutch bell some time ago this was causing the bottom clutch plate to bind and not release,anyway another way to see if your clutch is working correctly is to disconnect the cable then put a 19mm spanner on the clutch arm ,pull the spanner around as far as it will go then at the same time get someone to apply the kickstart and (note) if the kickstart slips nice and easy,if it does then the clutch is working fine and it means that you've not adjusted the cable correctly,(please note) most cables dont have any slack in them,some clutches take time to bed in and will need re-adjusting after a few miles.

Dean
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