Wobbly primary drive

cgrigson · Post by **cgrigson** » 18 Feb 2008 13:55

Hi,
My primary drive is rather wobbly and I want to replace the bush in the big primary gear. Has anyone ever done this before? What sort of clearance should I ask the fitter to set after pressing the new bush in? The bearing is about an inch diameter, looks like copper alloy on a steel substrate and runs on a steel sleeve. The bush has an oil groove. NLM said it was the first time they'd ever sold one of those bushes.

Cheers

Chris

EVguru · Post by **EVguru** » 19 Feb 2008 11:24

Hmm, have you actually had is all apart and checked which bits are worn?

cgrigson · Post by **cgrigson** » 19 Feb 2008 11:44

Hi Paul,
Yes it's all in bits. The sleeve fits the gearbox shaft snuggly. The gearbox shaft is rock solid but there is about .75 to 1mm wobble at the edge of the big primary gear when assembled. The surface of the steel sleeve looks unworn and has no steps. The surface of the bush is marked but not scored.... it's just rather loose. Most people like oilite seem to recommend a 1 or 2 thou clearence on this kind of bearing and it feels way more than that to me although I haven't got the tools to measure it. The clutch came with incorrect clutch plates and no plastic thrust washer, so the primary dive was just floating about. You can see the sleeve is lightly marked by the whole lot sliding back and forth in use.

Totally off topic I know, but are you still looking for a V7 / Tornado headlamp? There's a guy on ebay selling them sans rim for small money, search under CEV 137. Shop soiled and in need of a buff but good for the price. Rims can be had from the states for not too much.

Chris

EVguru · Post by **EVguru** » 19 Feb 2008 12:26

Some of these bushes can simply be pressed in and if the housing is correctly machined, will give the correct clearance. I'd just try it to start with.

I have a NOS headlamp shell, but I am still looking for a good rim. Can you point me to a source, most websites seem to have the 'wrong' rim. Mine uses a pinch bolt at the bottom.

cgrigson · Post by **cgrigson** » 19 Feb 2008 12:54

Hi Paul,
Alas the bush will definately need reaming.

Even further off topic I'm afraid...

Yes Wofgang Hearter at Columbian car and cycle is great to deal with and has the part. The Tornado light is the same as a V7 sport. He shows the rim here is it the correct one?

http://www.laverda.ca/Allitalia/allitaliaelectrical.htm

I can order two and save on postage if you like. I want to get the correct CEV 9313 tail light also after getting a simply rubbish repro through the post. DomiRacer have it here but I think the rim should be black rather than alu.

https://www.domiracer.com/comersus/stor ... uct=124113

What did you get with yours? $112 is a bit steep tho...

We should we move this conversation off board / or onto the Benelli forum?

Chris

EVguru · Post by **EVguru** » 19 Feb 2008 13:55

Alas the bush will definately need reaming.

I don't think I'd ream it, or certainly not by hand. The bore has to be absolutely centred and square.

I'd probably set it up on the mill and bore it to size.