Replacing Skorpion wheels with TZR

[maxgain]

Hi there all.

I was looking to replace my wheels with much lighter ones. I know that SZR wheels are much lighter and will do the job, however they appear to be very rare indeed and I never see any come up. I know Bill has mentioned TZR wheels will also do the job quite nicely. I have found that TZR's come up much more often on ebay and am seriously considering the swap with my original wheel. Now to my ignorance. Before I go and buy some, I would like to know a couple of things.

Will my original tyres fit the TZR, are there particular model years I should be looking at, will these wheels directly swap for my originals or will I need new spindals or any other new bits or modifications front and back. I am keen to do this as my current wheels have been poorly painted in the past. So if I am going to the bother of having them sandblasted and re-powder coated, I want to look at other options. And I dont want the bike off the road for a few weeks.

I had the swingarm re-powder coated two years ago but the rust is starting to come back quite badly. I am concerned about the integrity of the swingarm because of this. Again with this in mind I would like to replace it with something much lighter. Any ideas or suggestions much appreciated.

Regards

Stu

[handsomejackuk]

hi,

where can i get hold of a mz scorpion, looked on the usual places there seem to be none about. would love to get one as a track day bike...

did mz sell them in u.k. ?

[Norman Wade]

Two on British Ebay at the moment: http://cgi.ebay.co.uk/SKORPION-SPORTS-MZ-In-excellent-condition_W0QQitemZ300324209298QQcmdZViewItemQQptZUK_Motorcycles?hash=item45ecb7c292&_trksid=p3286.c0.m14&_trkparms=65%3A1|66%3A2|39%3A1|240%3A1318|301%3A0|293%3A1|294%3A50
http://cgi.ebay.co.uk/MZ-SKORPION-TRAVELLER_W0QQitemZ130314421415QQcmdZViewItemQQptZUK_Motorcycles?hash=item1e575844a7&_trksid=p3286.c0.m14&_trkparms=65%3A1|66%3A2|39%3A1|240%3A1318|301%3A0|293%3A1|294%3A50
Quite a few about in the UK, I know of about 10 at least in Scotland, and there's 30 members of my forum http://mzskorpion.mybb3.org/
Might be worth placing a 'wanted' ad there or on my website.

Norman
http://www.mzskorpion.net

[Bill Jurgenson]

Ok, You need the Belgarda 4DL wheels :
Front: 3/17" with rotor mounts on both sides. It is the selfsame wheel used in the SZR and the FZR400. This wheel fits as is but without the speed drive. The Yamaha axle is 17mm instead of the 20 of the MZ but like the MZ axle it has a 25mm bushing at the left and M16 threading so basically the the OE Yamaha axle can be stuck right in. You'll need to make a bushing to replace the speedo drive or better,a new 78mm long bushing to replae the OEM part and the speed drive together.

You can use the 2,75/17 wheel from the 4FL as well and if you mill 5mm off the inside of the left fork leg at the bottom even use the speedo drive.

new_front_wheel.jpg (68.17 KiB) Viewed 3213 times

You will have to make bushings to the center the caliper (5mm I seem to remember) or a spacer of similar thickness under the rotor. I don't recommend using this wheel but if one is dead set on retaining the original instruments...

Rear: both late models use the same wheel: 3,5/17. You must get the chainwheel carrier(cushdrive) from the 4FL and not that of the 4DL. There are at least 3 different carriers for TZRs but only the 4FL fits the Skorpion.

4FL.jpg (66.84 KiB) Viewed 3213 times

You also need the Paioli brake plate and Brembo caliper from the late TZR or SZR or FZR400. The brake plate was used in several other models as well. If you cannot find one, I can sell you one. I have a few I have stocked for such rebuilds. The MZ brake plate does not fit and cannot readily be made to fit, not without welding and remachining, none of which makes any sense at all. You can put drill out the threading in the Grimeca caliper and use that if need be, but I would take the opportunity to chuck it if you have not already done so. Brembo is P32F, probably the most common rear caliper there is.

The Yamahas, including bot the FZR and the SZR, use a 15mm rear axle, the MZ a 17mm. You have two options:
1)replace the two wheel bearings with 17mm ID and drill out all the OEM spacers (carrier-wheel inside-brakeplate) and the brake plate and use the MZ axle. Slight hitch here: the 17 ID bearings are 1mm narrower than the 15 ID which is no big deal beyond the fact the it slightly spoils the rotor/caliper alignment.
2)bush the chain tensioners down from 17 to 15mm and use a 15mm axle, leaving all the Yamaha stuff original.
You will have to make a new axle from 15 mm stock which is simple enuf; you only have to cut M14 threading at both ends after determining the length. The Yamaha axle is maddeningly just that much too short! I have used it once by making a special threaded clasp instead of using a nut.

special_wheelnut.jpg (69.41 KiB) Viewed 3213 times

I can definitely say it is not worth the effort. It does look good, tho.
I have done both ways several times and can sat from my experience that (2) is vastly preferable and simpler as well.
Preferable because all the parts are stock Yamaha except the two outside spacers. These are two simple bushings, at the left, the OEM SZR part an be reduced in width (±12mm) and used as is, at the right 4mm thick and at least 30mmØ, better 35. Make 3 of these and use the the other two as washers on the outside.
My Skorpion hast these wheels as described with Haidenau Cup racing tire in 110/70 and 130/70. Weighs in at 150kg ready to go.