Author Topic: Yamaha Evo 43mm Forks  (Read 2175 times)

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Offline mustanggrahame

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Yamaha Evo 43mm Forks
« on: September 01, 2012, 03:17:47 pm »
Hi, just after some information re eligibility of 43mm forks for the Evo class. My 250H has a set of 43mm forks off a later non Evo Yamaha. This has the brake backing plate holder at right angles to the fork itself. I have the correct fork leg and backing plate from a 465H. My question is about the length of the fork tube. Do I have to find a set of correct (for the H model) length tubes?
Cheers, Grahame
RT1, DT1F, MX100A, TY80A, YZ80D, DT125E, CR125RE, 1982 KTM125RV, 1985 Can Am ASE, 1989 YZ250WR, 1991 YZ250WR

Offline Nathan S

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Re: Yamaha Evo 43mm Forks
« Reply #1 on: September 01, 2012, 05:29:54 pm »
I'd always thought that the 250/465H upper legs were as long as the G parts, but I'm beginning to think the shorter type, as fitted to the J+ models
(and, if the H parts are as long as the G ones, then I'm f$%ked if I know what I've got on my bike!).
If they're shorter, then you've got no drama.

That said, it seems that 95% of Evo Yamahas are running the later forks with the horizontal brake lug, and/or external dampening adjustment. Nobody's ever seemed to care (even on this forum!), so I can't imagine a too-short set of upper tubes being a drama.


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Re: Yamaha Evo 43mm Forks
« Reply #2 on: September 01, 2012, 07:02:51 pm »
Later uppers are no good on H lowers unless you have the H damper rods Graeme (because of the adjuster at the bottom of the leg being bigger that screws into the damper rod) if that makes sense ???

The exemption may be j uppers as I don't think they had the bottom adjuster but they did have the horizontal lug for the brake backing plate. Check out the bottom of your forks. If they just have the hex bolt you might be able to use those.
As long as you have the angled lug I doubt anyone's going to worry about the tubes.  ;)

Offline GMC

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Re: Yamaha Evo 43mm Forks
« Reply #3 on: September 01, 2012, 09:22:08 pm »
What later forks do you have?
If I undersatnd the question properly and the forks you have are 'J' then they are the same.

Part # = 4V4-23110-L0-00
Part Description = INNER TUBE COMPLETE 1
Model Count = 4
YZ250H 1981 250 YZ250 Competition Motocross
YZ250J 1982 250 YZ250 Competition Motocross
YZ465H 1981 465 YZ465 Competition Motocross
YZ490J 1982 490 YZ490 Motocross Motocross
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Offline holeshot buddy

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Re: Yamaha Evo 43mm Forks
« Reply #4 on: September 03, 2012, 08:26:59 pm »
the only real diff between a k model and a h is the
brake plate angle  and a adjuster that doesnt work
finding h forks is hard there are more k models out there ,still
should be able to run them they are both about the same performance wise
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Offline Ando

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Re: Yamaha Evo 43mm Forks
« Reply #5 on: September 03, 2012, 09:32:31 pm »
The 81 & 82
Externally the 82 look different

« Last Edit: September 03, 2012, 09:36:40 pm by Ando »