CRF front in My '87

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DEATH_INC.
Posts: 6
Joined: Sat Nov 23, 2019 3:47 pm
Location: Auckland, New Zealand

CRF front in My '87

Post by DEATH_INC. »

So, I've done the unthinkable and changed out the front end on My 500. Not too many complaints with the originals, but the lower legs are prone to getting dented (both My originals and the spare set I got are dented) which causes 'sticky' spots, and I got some '05 450 forks etc for the right price (free).

Anyhow, the CRF uses 30 51 15 bearings, the CR 26 47 15. So there's an obvious difference there. The stem is also a few mm longer, you can't adjust it enough to take up the difference.

I looked at the option of swapping stems, but it would need sleeving to fit the clamp, or a custom stem, and still a sleeve on the top. Too hard. The 'easy' way would probably be to get some later clamps, but they too went to a bigger lower bearing. I'm not sure of the length either, and anything like that is hard to find here.

A little digging brought up the All Balls conversion kits, but of course none in stock here, and they're pretty pricey as well.

So the search began for the correct sized bearings, 30 47 15. No such animal, and I noticed AB use a 30 47 12. Found the number and priced up a couple locally...$120 each! Off to ebay, found some in England from Pyramid parts, who don't have a great rep for quality, but I figured I'd grab a couple and give them a go, at least I could see if it was all going to work. $75 for 2 bearings and seals.

Did a bunch of measuring etc and waited. Made some spacers.

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Once they got here I was pleased to see the NTN (and Japan) brand on them. (that one isn't rusty, it just crap off my hands)

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The spacers were to go under the bearing, and make up the 3mm in height. Once it was all fitted, I did a little more measuring and decided I could get away with a little thinner spacers, so made another lower a little thinner. The spacers are 47X40X1.9mmlower and 47X40X2.9 on the top. The thicker one to tighten the bearing down is 7mm thick. Tapered from 40-45 if I remember correctly. Doesn't need to be you just need to make it as round as the lock ring. I thought I had a pic of the bearing installed (i don't) but its pretty straight forward, just drop the spacer ring in, then press the bearing shell in behind it.

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Once it's all fitted up the next step was to check the steering stops, which don't connect, so your tank becomes the stop, which is no good. I contemplated a couple of different ways to sort this, but just went with the simplest way which was drilling and tapping for a couple of bolts.

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Not exactly a precision fit but they'll do the job.

That was pretty much it, the stock guard bolts straight on. I did drill and tap a 5mm hole in the top clamp to bolt the plate on (it's a very sturdy part of the clamp), and glued a lower mount on the back of it to fit the CRF lower mount. I do have the CRF front guard and plate, but I think they're fuggin ugly.

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I'm using the stock master cylinder (I don't have the CRF one) with the CRF caliper. Same front brake hose, though I had to carefully trim the stiffener a bit shorter. CRF front wheel of course, which I had already.

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Going by the state of the rest of the 450, I'll have to rebuild the forks before I use them much, which isn't all bad as I'll soften the valving a bit at the same time. The '05 450 has a rep of having stiff forks.

So, now just have to finish healing My shoulder so I can get out there and try them. It was a pretty easy conversion really.
:stretcher:
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