Late model YZ front in PE400

[Quicksilver]

I am toying with the idea of fitting a recently acquired late 1990's Yamaha YZ upsidedown fork front end into my 1980 Suzuki PE400. The YZ front is aprox 1.5 inch longer then the original PE however I will be dropping the rim size from 21 inch to 18 on the front so extra fork length shouldn't be a problem.   
I was counting on the late model front improving the PE's road handeling on tar road surface. The extra braking power supplied by the disc will be a welcome improvement. The PE will be running 18 inch rims front and rear with road tyres as the bike will be used 98% of the time on puplic streets. A spare pair of wheels with wet weather racing tyres will also be prepared for local oil track rides 6 or 7 times a year.   

Has anyone done this sort of thing before? Any pit falls I should know about? Please offer any opinions for or against this swap in regard to handeling improvements.

[rls840]

Sorry mate, I can't be any help on the technical side of things, but it does sound like it'll be a wild ride. Good Luck.

[Quicksilver]

What! 
No one has ever put late front end into an old bike! Find that hard to believe.

[LWC82PE]

this bike was on ebay over a year ago. Someone on this forum bought it and sourced the correct PE forks for it, then i saw it on ebay again. i have no idea who has it now but it had ohlins shocks with red and blue fittings on the hoses.

I remember the first time it was sold on ebay the seller said the front end was RMX250 USD forks.

[jimg1au]

drew
i put a late modle suziki front end in my 1979 it400.it wa great and stopped well.machined the suziki tripples so they fitted the it headstock.made spaces for the bottom bearings to sit on and bolted eveything up.look what stearing head bearings you can get to match your headstock and tripples and go from there.
i even have gtmx80 forks and alloy tripples in my hagon slider
cheers
jim

[Marc.com]

I would be struggling to think of a better road bike , but of course everything fits everything and the front end will fit, just whip up a new steering head stem, I just fitted Simons forks to XL250 frame and it was no problem. Why not.

Another option is to fit a GSXR front end and lengthen the forks, that way you can run 17" tyres.

[Quicksilver]

Thanks men  . I may have look for other claims the bump stops for Yamaha are in a completely different location. RMX might be the go.
LWC, that PE looks ok with later front end. Disc a lot safer for round town road use then the old drum.

[Quicksilver]

I think it might be best to use a Suzuki front end. The bike has been sitting gathering dust for a months. Time I get it out and continue working on it.

The plan is run wheels something like these.

[frostype400]

I have a project one that I am sourcing a front disc end for it would be a great bike to ride in the high country with my uncle and still keep up with the new stuff and have peice of mind when you look at going down a big hill you can stop thanks Michael.

[Quicksilver]

Does anyone know where this bike went? I would like to talk to owner about the front end or the person that fitted the front end. The YZ front is not gunna work in the PE. Spent hours this morning trying different things. YZ clamps are the wrong shape and hit the tank way before full lock, even tried a smaller RM400 tank and still had the same problem. Would be fine if you only wanted to ride in a straight line.

[Quicksilver]

AT LAST. A front end that fits. I tried 7 different models/brands of front ends today the solution was 41mm TS 250X disc brake front. From bottom clamp to axle lug is aprox 2 inch longer on the TS then the original PE, perfect for fitting an 18 inch front wheel. Not quite the type of front end I had planned on using but it will have to do for now

[frostype400]

I will have to keep an eye out for a ts250x front end is that the original triple trees? becuase arent the original 36mm or did the ts triples sit straight on thanks alot Michael.

[Quicksilver]

Nah frosty, it all ts including the clamps. Just gotta find TS250X headlight, speedo and stuff to mount on it now.

[LWC82PE]

Are you sure they are TS250 forks? i thought they were all 38mm, well at least 84-87 and from the measurements Doc gave me they had less travel than the standard PE forks.

[Quicksilver]

Hope so......... They were marked TS250X in wreckers yellow pen.  Everthing just fitted nicely. If not TS250X what do think they might be?