V90 to disc brake conversion

[hedgeling106]

Can I put pk XL forks on a v90 without modification.
Will I need px hub?
Would et4 hub fit? Though it may be look a bit odd could then have tubeless front wheel
How do I convert 90 headset to accept hydraulic master cylinder, have et4 master cylinders would they fit.
I know it's old topic but new top me.
If I keep four bolt wheels and buy new parts for disc conversion and tubeless wheels, what's it gonna cost.

Got shed loads of et4 and PK parts, and few px parts

[jbcollier]

You ask a lot of questions in one post.

1) Yes and no. It will fit but you will have to sort out a few issues: fender mounting, shock clearance, ride height, wheel offset, etc.

2) If you want a disc brake, you'll need a disc hub.

3) Will X, Y, or Z fit? Anything can be made to "fit". Will it just bolt on and be perfect? Are you kidding? No.

4) You can weld a plate on the headset, fit an adaptor, etc. I extensively modded mine and fit a radial master.

5) Cost? Depends on which route you go and how much you do yourself. I didn't know that they made tubeless 4-bolt rims.

There are now bolt on kits for the original forks. I prefer the PKXL system but the bolt-on kits will be less expensive.

[hedgeling106]

Ok l knew I shouldn't of asked, do PK hubs fit on v90 forks, is spindle same size?, or same as px.
Could l change v90 engine for PK 125 engine and PK front hub and have tubeless wheels. Did read PK brakes better than v90 brakes.
Would be simple upgrade, or if I go down pkxl route could I find somebody to mod them for me.

[triffid]

not sure on the hub exchange, you can fit pk engine into your 90 but will need different carb manifold and exhaust to avoid fouling on the frame and will need to make sure electrics are the same so need to ensure you have same size crank taper if you are going to fit v90 stator and flywheel. SIP might now do tubeless 4 bolt rims, I know they do for 8 inch wheels.

[jbcollier]

Early and small engined PKs use the standard smallframe front from/drum/etc. PKXL125s use the "mini-PX" fork with a 20mm axle of the later PXs. The Early P hubs are for a 16mm axle and will not fit.

The PKXL125 drum front brake is actually quite good.

[hedgeling106]

I have a 1982 pkxl 100 forks and pks 125 engine, so will forks have 20mm axle, what size is v90 front axle. Oh and is PK front hub nut lefthand thread, like v90, don't want to bugger it up.
Thx

[jbcollier]

PKXL125 forks look like this:

www.sip-scootershop.com/en/products/steering+column+rms+for+vespa+_13333000

I don't know if the PKXL100 comes with the older forks or the above. You can answer that, though.