fork question

[B2]

Does anyone know if swapping 92 forks into an 89 KX500 will require replacement of the triple tree and brake caliper.  The part numbers are different for each, but I think the conventional 89 forks may have the same size triple tree as the inverted 92 forks.  Also, any guess on the brake caliper?  Would the 92 inverted units be considered superior to the 89 forks, which were at the end of their development cycle?  Thanks, Kenny

[Arigato]

I'm not sure about the brakes, but you would definately need new triple clamps.  Inverted forks flex a lot less and you would have access to a lot more valving options.

[John]

You need new tripple clamps and you need to fit them to a old steering rod (?)  since the new one has a larger diameter.

You will also need a new mounting bracket for the brake caliper or alternativly a new brake caliper - probably cheaper.

I suggest you search the forum since there are some old posts about this subject.

I have done it myself and it cost me more money than it was worth. Try to get hold of an old rolling chassi instead.

//John

[B2]

I have procured parts and will be moving forward with the conversion as time permits.  As stated in the above post, my bike is an 89 with conventional forks and I will attempt to fit 93 inverted forks.  My 89 triple tree has an ID of 45mm and the seller of the triple tree for the 93 claims a 54mm ID, so this is a must change.  I hope the steering stem sizes are the same, as I do not think they changed until the forks were significantly updated in 96 or 97(?), but it's hard to know for sure without parts in hand. 

The brake caliper mounts looks different so I will replace the caliper, but the brake line and master cylinder show the same part number for both years and should not need replacement.  Also, the axle shows the same part number between these years and will not require replacement, so the same wheel can be used, but new collars may be required to space the wheel properly. 

Rick's post on points to consider when doing a fork swap was informative.  It would be nice to have a cross reference chart or something to know which parts could work from 125 or 250's as well.  It's hard to tell using online microfiche.

Any other opinions on the early generation inverted forks compared to conventional units?

[Murrdogg]

I made plans to do this to a '89 kx250 that I picked up a few weeks ago as a restoration project. From what I have found so far, an '89 kx250 frame is the same as the kx500 from '88 to '04. I would like to put the whole front end of a kx500 on the 250 frame if it will accept it without having to frankenstein anything.

[ninja]

... Would the 92 inverted units be considered superior to the 89 forks ...?

Do a lot of climbing & sand.  I like the conventional fork with a lower front balance. 
89 forks had internal fixed re bound & the top screw is a bleed valve + valve cap on top of fork I use 0 psi or atmospheric pressure