Sticky starter

The Cagiva era Morinis

Re: Sticky starter

Postby 3potjohn » 02 Oct 2020 10:08

Had a bit more time to investigate a slight or not so slight whine more noticeable on the overrun.That may be a red herring as the silencers are fairly brisk.I should state this is a Coguaro not a Dart but has broadly the same system.
If I run without the sprag gearset the sound is eliminated. Well it was once I mastered using the kickstart which is a bit on the high side.
Upon reassembly the only bearing I removed was the inner flat roller. So it could be reversed but I did not identify its orientation. When bolting the cover back on I tried inserting and tightening the bolt running through the gear shaft first before the other 2 long bolts and the three short casing screws.
Whine eliminated.
I found this before by accident.I do not know if the flat roller or the sequence with which the casing was tightened is the cause.
The top and tail of it is I want to source the flat roller bearing.
Measuring with the trusty Alidi caliper (!!!) I make it 27.5 OD ,1.96 thick with 12.1 ish ID. Simply Bearings do one that’s 28mm by 12mm by 2mm . For the approx 3 quid it might be worth it except that ID is the same as the shaft diameter
If anyone can confirm the measurements it would be helpful.
John
3potjohn
 
Posts: 751
Joined: 02 Jun 2007 13:58
Location: Devon

Re: Sticky starter

Postby morini_tom » 03 Oct 2020 08:52

I still think you should reduce the thickness of those probably not original 1.5mm thrust washers by replacing with some new as per my last post- firstly because the gearset will be shimmed wrongly, and secondly because the thrust washer is hardened and intended to take the axial loading the helical gear imparts, and your 1.5mm ones may not be.

For 3 quid it is also replacing the needle roller thrust bearing (and I'd probably replace both of them incase they have both been damaged by the incorrect shimming- if one is whining then both could have been damaged in the same way). I don't have any spare unfortunately. There were some NOS ones on eBay a while back, but I think they were about a tenner and in the USA.

Just measured my needle rollers up at 12.09 id and 25.71 od, 1.95 needle diameter- I think your 27.5 measurement may be a typo?

Closest I can see from a quick search is https://simplybearings.co.uk/shop/p8796 ... _info.html

The below link is a set that looks to be the thrust bearing, and 2x 1mm thrust washers- so two of these kits would do you, and as I said in the previous post, I would use the 1mm thrust washers on different shafts, with the thinner of your original thrust washers on the other ends to split the thickness difference as the original thrust washers were 0.95mm
https://simplybearings.co.uk/shop/p9626 ... _info.html

Let us know how you get on,
Tom
morini_tom
 
Posts: 601
Joined: 05 May 2006 13:47
Location: Northampton

Re: Sticky starter

Postby 3potjohn » 04 Oct 2020 21:31

Thanks again for this. I will let you know the outcome.Bled front brake today. That furry alloy reservoir cap was nice.
John
3potjohn
 
Posts: 751
Joined: 02 Jun 2007 13:58
Location: Devon

Re: Sticky starter

Postby 3potjohn » 07 Oct 2020 11:52

Got the items as described from Simply Bearings.Exact match for the thrust washers and thrust bearings.Bit of swapping around but now just a barely audible sound.This may be as good as it gets.
Nodded wisely at those six cush rubbers which are intact.For now!
In spite of the malarkey various have managed about 1200miles since June mostly in the many lanes of Devon.
Thanks for the help.John
3potjohn
 
Posts: 751
Joined: 02 Jun 2007 13:58
Location: Devon

Previous

Return to The Darts

Who is online

Users browsing this forum: No registered users and 1 guest