Posts
5768
Joined
11/25/2007
Location
Athens, GA
US
Fantasy
4173rd
queen of spodes
9/3/2018 8:26pm
9/3/2018 8:26pm
Edited Date/Time
9/24/2018 8:30am
Just picked up a 1987 KX250-E1. Bike is rough, but it was about to be parted out. Plan to put a minimal amount in and enjoy it as a vintage racer.
Fork seals died years ago.. forks have no oil and are springy, so they need full rebuilding.
Are USD forks illegal in EVO 4 class? I ask because KTM had them on their bikes. I also have a pair of 41mm USD's from a 1991 KX250 in my shop.
Would I be better off restoring the 87 conventionals (assuming I can even find bushings) or should I upgrade to the 91 upside downers?
Fork seals died years ago.. forks have no oil and are springy, so they need full rebuilding.
Are USD forks illegal in EVO 4 class? I ask because KTM had them on their bikes. I also have a pair of 41mm USD's from a 1991 KX250 in my shop.
Would I be better off restoring the 87 conventionals (assuming I can even find bushings) or should I upgrade to the 91 upside downers?
Race Tech Cartridge emulators are another option, but I think you could find the 88-89 forks for less than the emulators will cost.
You will also want way stiffer springs. I just put stiffer springs in an 86 YZ 125 and even with no other mods, the damper forks actually aren't as bad as I expected them to be. They are KYB, probably very similar to the ones in your KX.
I rode a friend's 86 KX 250 earlier this season. If the 87 engine is similar, you are in for a treat. It had a nice usable bottom end and respectable over rev. It was very easy to use and fun to ride. Ergos were a bit weird haha but that's pretty much every bike before 1989!
I checked on the parts fish and the front wheel/brake setup is the same on the 87' and 88'. So it would be easier to throw a set of 88' forks on that bike, and you wouldn't have to change anything else. The 88' forks were cartridge forks, but were the standard 43mm, so they should slide right into the stock 87 triples.
Also, you can still buy stiffer fork springs for the standard 43mm conventional forks. Stiffer springs for the 89' 46mm forks are hard to come by.
Just some things to consider.
The Shop
I used their kit when adapting a complete 03 CR250 front end onto a 89 CR500. Worked like a champ.
I didn't like the gold anodizing on the lowers so I spent forever with them in a sand blast cabinet. It was son of a gun to get off.
If I were to do it again id go for a 89 front end
Where did you get that trick silencer? I need one those?
Post a reply to: 1987 KX fork update/swap?