Light weight top gear gear modification

Circlip · Post by **Circlip** » Sun Aug 12, 2007 4:21 am

I recently discovered a rumbling kinda noise coming from --well somewhere On my 62 AJS CSR14. With screw driver as a stethascope I located the noise to be around the gearbox. I decided to pull it out.

Everything was ok exept the two bearings. Well the main shaft RLS 4 was easy. got that from the outboard motor dealers.

The top gear/ fial drive cluster was a bit different the inner bearing race is part of the cluster and it was pitted. It should be a RNU 205= 52,OD /32,ID. But instead out of mistake more than management and poor language skills I orderd a NU205 this bearing is 31.5 ID( I found out)

With vernier and bits in my hand I decided to have the shaft cluster machined to fit the bearing. this will also put a new surface on the cluster. I am concerned about the case hardening but it only needs .25mm to be removed from the old surface.

Ok all going well so far,-- however the rollers are 9mm instead of the standard 6mm in length. This means I have to cut into the location shoulder of the cluster by 1.5mm and 1.5 mm on the oil seal sleeve.

The seal too was imposible to obtain. The od was near as damit metric so the sleave was cut down to fit the seal.

I get the gear back today at 3pm,- you guys will still be in bed.Sunday morning lie in,--- listening to the Church bells.

This bearings is in very light use in comparison to what the bearing was expected to take. Pulling on a chain only when accelerating with 250cc would be well considerd to be extremely light use. All load is radial as the cluster is slid upon the mainshaft.

Edited by - Circlip on 12 Aug 2007 03:27:50 AM

Biscuit · Post by **Biscuit** » Sun Aug 12, 2007 12:46 pm

An owner in the future is going to love you!

Circlip · Post by **Circlip** » Sun Aug 12, 2007 4:41 pm

I would imagine this gearbox to go another what say 50,000 miles?

The final gear bearings is now a common NU 205 ECP and the rollers are heavy duty. The machinist did a fantastic job and the gear cluster has another life. If a new owner wanted he could turn it all back to standard. I have no Idea where I could get a final gear cluster.

Is'nt this part of owning an old motorbike,--its certainly the bit I enjoy.

I tried to down load a photo of the machinist work so others could revive old parts but I don't see how to down load it.

The machining cost approx 3 pounds 20 pence, and the bearing was 8 pounds, the seal was 1 pound 50 and machining the seal sleeve cost 1 pound 50.

Circlip · Post by **Circlip** » Mon Aug 13, 2007 8:42 am

Well shes up and running. No oil leaks and I have adjusted the clutch to just not slip when kicking her over.

This was a very enjoyable and rewarding exercise. Living on an island off the west coast of Malaysia means I do not have spare part dealers available. I have no idea where I would get a cluster from, but now I dont need to.

Here most things are repaired,machined or welded,--its just like the old days. I do not understand the comment " the next owner will love you" I can only assume that when you do it for money you loose the love of it.

The older the machine, the more skilled you need to be to keep it going,--isnt that the fun?

bag-o-nails · Post by **bag-o-nails** » Mon Aug 13, 2007 9:59 am

Hello circlip
you are i think lucky to have local enginers who
who are willing to take on a minor job like that
in the uk small companys that will take on a small job are few and far between and the cost probably £60.00 an hour!! I think most of
us here would just find a replacement box well done for a clever job, just a last thought most
spares can be obtained from the club or is post impossible on your island?
cheers b-o-n

Circlip · Post by **Circlip** » Mon Aug 13, 2007 3:51 pm

Thankyou bag -o -nails i was begining to think I was talking to myself. I can get stuff posted here and it is a duty free island ( beer cheaper than water) but where would I begin to look for a final drive gear?

I bought the bike as in a box 15 years ago for 50 quid its not original, the spokes for instance are long screws bought from the most incredible screw shop in China town Bangkok.

The gearbox was missing and I Picked one up in Wigan some where 10 years ago.

bag-o-nails · Post by **bag-o-nails** » Mon Aug 13, 2007 4:46 pm

I think i am very Jealous tropical island, beer cheaper than water!!!
Try Tony surben AMC Classic spares e-mail
tony@amcclassicspares.com fax 01462 811770 if he does not have it in stock he will find it for you, Very Helpfull chap. I suppose you live on a beach !!!
cheers
b-o-n

Circlip · Post by **Circlip** » Tue Aug 14, 2007 3:45 am

I will keep that number B-o-n but I hope I dont need it. Ide rather fix it.!!! ta very much.

I was going to have a chug around on it today but,--- I think its going to rain the insects have shut up and the monkeys have gone quite too. The little sods steel the valve caps,--would you believe it.

You dont get that trouble in Basingstoke.

Eamonn · Post by **Eamonn** » Tue Aug 14, 2007 8:39 am

quote:
I tried to down load a photo of the machinist work so others could revive old parts but I don't see how to down load it.

Send me an email and I'll help it.

Eamonn

Circlip · Post by **Circlip** » Wed Aug 15, 2007 5:37 pm

Oh Oh got a bit of a problem. The gearbox selects beautifully down but going up I get false neutrals--not all the time just most.

If I select twice it selects, --bit messy. Ive left her in the car park until I think about it.

With engine off it goes easily 1234-4321
And its better at low Rpm than high???

Has anyone any Ideas.