fork interchangeability

pilninggas · Post by **pilninggas** » Sun Jul 05, 2020 4:08 pm

Hi Guys,

So - i have posted about this before - my Exup (95) keeps blowing seals. To the point where i can change them in about 30 mins.

The bushes are worn and due to the unique* way they are produced, the bushes cannot be changed (they are prepressed into the outer tubes).

I have just got a set of 91-93 forks which do have replaceable bushings from the bay, so what else will i need to change to fit them? the axle looks the same part, as does the lower triple, but what about the top? will that need a new part? does anyone have the bits i need? cheapish?

TIA

pg.

Teego · Post by **Teego** » Sun Jul 05, 2020 7:43 pm

PG, I assume that your 95 is an RU. Are the stanchions clean and unpitted? When I had forks refreshed the guys polished out the imperfections.
Also IIRC Suzuki seals perform better than Yams. Don't know which model but I'd just check fork diameter.

pilninggas · Post by **pilninggas** » Sun Jul 05, 2020 8:26 pm

Teego wrote:PG, I assume that your 95 is an RU. Are the stanchions clean and unpitted? When I had forks refreshed the guys polished out the imperfections.
Also IIRC Suzuki seals perform better than Yams. Don't know which model but I'd just check fork diameter.

The stanchions are pristine and definitely not the problem. The bushes are worn and cant be replaced. It's bloody annoying.

Post by **Stig** » Sun Jul 05, 2020 9:58 pm

Could you fit the earlier bushings in your forks?

pilninggas · Post by **pilninggas** » Mon Jul 06, 2020 7:12 am

Stig wrote:Could you fit the earlier bushings in your forks?

you can't access them - they are in a 'rebate' in the outer tubes and cannot be retrieved. It's a terrible piece of engineering, but i guess yamaha assumed they would last 50000km and so didnt think to worry about the time after that.

pilninggas · Post by **pilninggas** » Sat Jul 18, 2020 4:13 pm

An update - got the 91-93 forks. These kayaba units can be rebuilt. I havent given up on the ohlins oe - im gonna see if i can do anything to re-bush them.

Managed to get some decent mild tubing to space the axle 17mm to the required size for 94/95 wheel - just need to remove 0.2mm from the Od, so ill do that on the lathe in work next week.

But i need an 91-93 (poss 89/90 also?) axle. Does anyone have anything really cheap? I have an XJ600 axle which is the right od but is 15mm too short. balls.

Post by **Stig** » Tue Aug 11, 2020 10:26 pm

Had a look and sorry to say not got what you want

pilninggas · Post by **pilninggas** » Wed Aug 12, 2020 3:58 pm

Stig wrote:Had a look and sorry to say not got what you want

thanks for looking.

Post by **nuggitt** » Tue Aug 18, 2020 11:49 am

Seeing as its raining today and I can't get out to play. I decided to take out my front wheel just for you pilninggas.

I've taken some measurements of the axle and you're correct so you can discount the 89/90 axle from your list.

pilninggas · Post by **pilninggas** » Tue Aug 18, 2020 7:10 pm

nuggitt wrote:Seeing as its raining today and I can't get out to play. I decided to take out my front wheel just for you pilninggas.

I've taken some measurements of the axle and you're correct so you can discount the 89/90 axle from your list.

Thanks for that - that isnt long enough and must be from an 89/90.

I've got 2 that length (one from a TDM850 i had years ago and one from an XJ)