Project Yamaha SRX 250 3WP

Well, my curiosity got the better of me... I found a set of Aprillia RS125 USD yokes for a reasonable number of rubels.
Based on info from @ruckusman and some others on the interwebs it appears the offset and fork spacing may be the same as the SRX. The head bearings are different so the stem will need modification but thats not a big deal and there would be plenty of time to figure it all out.
Now to just wait for a cheapish (its all relevant I guess) set of Aprillia USD forks to materialise.
Unless there are other 40mm USD forks that could fit the yokes????
What on earth am I thinking???????????

 

Just had a look at your old thread about USD forks and it looks like they are 50mm and 52mm but I will confirm that when I get the triple here...
I am no rush, I will probably need to get an Aprillia front wheel as I dont know if the 3WP wheel and be modified to fit the forks.
It only has a 15mm axle where the Aprillia is a 25mm I think.
Who knows, it may be a waste of time but I probably wont lose any money on the triple clamp.

 

Hmmm, infortunately the front wheel bearings are B6301 which is 37 x 12. I have the 3LN1 wheel but it is set up for 2 discs (as we know). That will all be a little way off yet. This will be a longer term thing (This build is challenging @maelstrom for glacial speed).
Information gathering along the way.
At least I will have some info to add to the USD Database.

 

Yes, I had it in my head it was 15mm and 17 for the FZR250 but my memory isnt quite what it used to be...

I guess if I use the Aprillia front wheel then I can maintain the speedo drive (if the gearing is correct) and proper spacers etc.

 

Interesting... as the FZR isnt what I would call a lightweight wheel.. aspecially with twin discs... they arent light either.
Something like this would be good... looks the part anyway.

 

That front wheel is an Aprillia wheel.
$226 on Bay of Fleas plus freight.
I would probably lean more to the Aprillia just to maintain the ease of swaping over. no having to make special spacers etc.
Geometry is all pretty much spot on... If I am going to do it I want it to be a straight forward swap.
At the moment it really just seems like it is some machining to sort out the stem bearings, the rest seems to be pretty easy.
But I am not in a rush at the moment. Lets see what the triple tree is like when it arrives.

 

I really need to STOP looking at eBay... I found a set of RS125 forks, they will need a good tidy up and there is a little bit of pitting very low (out of the seal area). Ony issue is they are in the UK. I have made an offer on them.. but it doesnt make much of a change in price... should be able to get them here for A$180.00 all up.
Thats so long as my offer is accepted lol.
Based on the pricing of complete front ends in eBay I could make money on it all if I dont end up using it.
This modification stuff is a very deep and dark pit.... lol

 

I can ONLY use the front... Aprillia have the chain on the RHS so the Cush drive and also rear brake mount are wrong for the Yamaha... but that is OK.the earlier front wheels are 3 spoke similar to the SRX250 3WP and FZR so it wouldnt look out of place.

 

@maelstrom, @ruckusman I can confirm that the Aprillia RS125 forks are 180mm centre to centre with a 45mm offset.
Bottom clamp is 54mm and just waiting on the top to arrive and I can then confirm that as well..
I also now have a set of forks on the way from Old Blighty... so then I will be able to measure fork length etc as well.

 

Oh I have been in deep for a long time on the SRX... This will be the 3rd front end, the 250 engine, 350 engine, rear shock, rear swingarm and rear disc, 3WP tank and rear fairing, FZR250 rear wheel, 3WP gauge cluster and wiring loom...
I should have stopped earlier as that is depressing really lol
In the end, it is still the little SRX250 I bought way back in ......Feb 2016, but new bits everywhere... including the frame lol

 

I have been away for work for a few days and this was waiting for me when I got home.


I resisted the urge to measure it up last night.. but I can now confirm the top fork mount is 50mm.
While it looks black in the picture it is almost a dark bronze in real life.. might have to see about getting it done in Ceracoat if I end up going ahead with the conversion.
The forks are on their way... estimated around April 11th from Ol'Blighty.