Running gear upgrade

[fozzymz]

I won that MZ racer on ebay.

First things first, suspension and wheel upgrades.

I was thinking Aprilia RS125 complete front end and Mito 125 rear wheel.

What are the alternatives/easy options?

[OLDMTNCARVER]

Congrats on your purchase!
I was following that one...
I think I remember ( disclaimer ) Bill saying that an R6 front end would work without much work...
Regards,
Rob

[Bill Jurgenson]

The Paioli RSU fork is much better than many others, even if it is not adjustable. Don't fool with that to start with.
Get a modified CDI or have the one you have modified to at least 8400 and change the gearing to at least 41 at the back if that hasn't already been done. While you're at it, reverse the shift pattern to first gear up: simply stick the change lever on the trans shaft the other way round. Better yet, get an XT shift lever and stick it directly on that shaft.

xt_lever.jpg (69.94 KiB) Viewed 5808 times

Fit decent clipons under the triple tree and, if you are running the stock carb, the single wire Tommaselli short stroke gas grip; the stock carb does not need the two wire set up at all.

Ducati Griff -Toy.jpg (67.42 KiB) Viewed 5807 times

Gilles GP Light Clipons with that Tommaselli grip, Ducati on/off switch, and Brembo PS16 pump.
And very first of all if it hasn't already been done, throw the Grimeca shit away - as far as you possibly can, all of it.
Ride the thing with the new CDI and shorter gearing and learn to ride smoothly; shop for the right wheels without getting stressed.
Next, mount a really good strut -Wilbers or Penske or WP made to order, giving them your weight, the total weight and the usage (track). If and when you order that strut, order linear springs for the fork to go with.
First things first and that means good wheels once you have mounted the best strut you can get. The Mito does not have good wheels (Grimeca again!) nor is there any other advantage in using them as they are the same size. The RS125 has downright crummy (Grimeca yet again!!), heavy wheels and the chain is on the wrong side, too. Aprilia RS250 (AKA SUZI RGV) would be fine, tho, and are a common choice. Only for racing, tho, since most 2-stroke wheels don't have a cushdrive.
You need a 3,5" front and a 4,5" to 5,5" rear, not wider.
Here again, R6 is probably easiest. Best would be FZR400 or even better very late TZ250RR 3MA. Scarce as hen's teeth but not impossible. For the front almost any FZR. I can offer a FZR Bembo 3,5"/17 front skimmed down to fit the fork. was used in a TZ250 before I bought it and I used it for the rain tire. Virtually all Yamaha Wheels are Brembo wheels: Brembo belongs to Yamaha!!
All this assuming you are unable or unwilling to fork out for new racing wheels. If you can, go magnesium. Easiest is then Dymag who will deliver plug an play for the Skorpion. I used Marvic myself.
When you get this far and know the lowly Paioli fork is holding you up, then look into that problem but not before. as you can see above, I still had the RSU mounted in that bike and I know Chris Hunsicker does, too.
Both an early R6 RSU and the Kawas 400 RSU fit the triple tree, both are adjustable and for both it is easy to get springs. I have the KAWA fork complete which I could sell. The KAWA normally has a 3,5" front wheel and 280mm dual rotors.
For later USD forks, you need to adapt the triple tree or have one-offs made to fit. The Aprilia RS125 is definitely NOT the one to choose.
Most any 50 - 54mm will do: FZR, Ducati, you name, but it is NOT plug and play like using a 41mm RSU is and the 50mm USD has 41mm tubes just like your lowly Paioli does. I have personally fit a Paioli USD and a Showa USD (from Aprilia Tuono) using the triple trees belonging to those forks and my own bike has one-off billets. For the stock triple trees, you have to change/remachine the steering tube to fit and this is not a "basement" job.
here is the Showa with its Aprilia trees and new, shrunk-in tube which I made from stock and with PVM 3.5" front wheel mounted

put_together2.jpg (69.53 KiB) Viewed 5804 times

one advantage of using a modern fork is definitely the possibility of mounting a state-of-the-art caliper like the Brembo P34 with 4 individual pads.

The other Brembo with 65mm bolt pattern is not as good as the P30/34 you can mount on the stock fork, so don't.

this is the one to use:

obviously, the one for the right side, tho.

[fozzymz]

Thanks for the reply Bill.

I've already found the Dyamgs although £1200 is a little steep.

I've been racing F400 for three years so I know my way around a bike. My first season was on an FZR400RR, I should have kept the forks.

I don't want wider wheels, a 110 front and 150 rear is more than adequate for me I think. Thanks for all the tips.

I see a guy in Monaco is selling Wilbers shocks, are they up to the job?

I've used Maxton and Ohlins in the past, the forks on my ZXR were re-built by K-Tech.

My friend is delivering the bike in half an hour so should know more then.

[fozzymz]

Wheels first then Bill? I'd better get the credit card out.

[Bill Jurgenson]

Wilbers is in my opinion as good as they get.

Yo are going to need the slightly wider wheels 'cause there are very few racing tires that fit. Pirelli Supercorsa and maybe Michelin Pilot race. No slicks at all.
At the back, you need at least 4,5" even to run the 150 tire. The 4" rim is too narrow for a 150 tire according to the tire manufacturers. Pirelli gives 4.25 as reference rim and Bridgestone 4,5" for 150/widths.
On the street I run 110/60 front on a Bremb 3/17 and 150/60 on a Brembo 4,5/17,. both from the TZ 3MA. I see you are in the UK There were a lot of TZs raced and there are a couple of specialist shops, so it could very well be possible to find the 3MA wheels.
Right now at eBay UK there is a pair of FZR400RR wheels - exactly the right ones for you:
http://cgi.ebay.co.uk/Yamaha-FZR-400-RR-SP-3TJ-Wet-Rain-Tyres-on-Wheels_W0QQitemZ140212330650QQihZ004QQcategoryZ10490QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[ZzerO]

if you are running the stock carb, the single wire Tommaselli short stroke gas grip; the stock carb does not need the two wire set up at all.

Bill,

can you use the original wire with the short stroke gasgrip?

and would this model fit the skorpion?

http://cgi.ebay.de/Domino-Gasgriff-Comm ... dZViewItem

[fozzymz]

Got the bike.

It already has quick action single throttle cable.

Right, I'll try the FZR wheels Bill.

[Bill Jurgenson]

es you can use that grip but I sure wouldn't; too big, too complicated. And more expensive.

check this page for several possibilities:

http://www.redracingparts.com/en/english.htm

all from Domino/Tommaselli

the one I have costs all of 20€.

[Bill Jurgenson]

es you can use that grip but I sure wouldn't; too big, too complicated. And more expensive.

check this page for several possibilities:

http://www.redracingparts.com/en/english.htm

all from Domino/Tommaselli

the one I have costs all of 20€.

[ZzerO]

thanks for the link!

does the gasgrip have a 'pin' that locks in the hole of the clip on? like the original gasgrip does?

greetz



ps. sorry for the offtopic

[Bill Jurgenson]

no, it doesn't, but it doesn't need one, either. It has a firm grip and the threads don't strip - it's not junk like the switch on the Skorpion.

[ZzerO]

ok thanks

[fozzymz]

which model R6 forks?

does the whole front fit?