Boxerworks.com

I just received my 1000cc Power Kit from Motoren Israel yesterday. Very high quality (TUV tested and certified), 9.5:1 compression, light weight pistons, Nikasil, manufactured by Siebenrock......but much cheaper.....at least for the next few days. They now have a kit to fit pre 1975 97mm spigots and small chamber heads. Time to make that R60 run with the pack, if you have any cash left.
http://www.motoren-israel.com/products/ ... cab2a95c13

It will be interesting to see how the weight of the new light 1000cc pistons compares with the stock 900s.

Garnet wrote:It will be interesting to see how the weight of the new light 1000cc pistons compares with the stock 900s.

I don't have a scale with that sort of accuracy. I do have a very good old fashioned balance scale. If I can find some gram weights I might get pretty close. The Germans say they are around 150 grams lighter (each). I'm not sure if they meant lighter than 1000cc pistons or 900cc pistons. They always keep their emails very brief. I'm currently attempting to get the installation guide in English. So far I've learned that the cylinders are to be installed without an aluminum shim (gasket) or main o-ring. Just use a sealer and 2 o-rings for the top studs. I'm thinking I'll use Dirko.

mattcfish wrote: Just use a sealer and 2 o-rings for the top studs. I'm thinking I'll use Dirko.

Oh goody... a Goop thread!

YOU! mean to say I can up my /5 to 1000cc with out boreing the case?

and have Nicksil........... OH BOY!!!

Motorhead wrote:YOU! mean to say I can up my /5 to 1000cc with out boreing the case?

and have Nicksil........... OH BOY!!!

...........you'll need to upgrade your brakes again Lyman!

I have a r90/6 that is undergoing an engine rebuild, bike will include the motoren Israel lightweight pistons with original cylinders, the idea is to end up with responsive engine that gets fairly good fuel efficiency, so the spec includes taking some weight from the flywheel a balance to include clutch assembly, twin plugging and litle cleaning up of the ports, together with the later lower sump, with any luck the engine should be ready in January. Otherwise the bike will look stock, can't wait to get it on the road and to see how the engine compares with my fake 90/S. Charles

Very cool!
What is the reliability of this kit? has anybody put one to the test?
I never knew they existed and i am now seriously considering one for a R75/5 engine rebuild. But i'm highly concerned with reliability.
Also, does the cam or anything else need to be upgraded as well?

I dought if there would be any reliability issues with these kits, the components are made in Germany by the saw mainstream manufacturers that make the oem stuff. I would consider that with a 9.5 CR, you might find that twin plugging would reduce pinging. I have a 1070 seibenrock kit on my other bike, no issues in 2 years.

It says a modification at the cylinder foot is required but the same head should work. What kind of modification? Boring it out a bit more? Will bigger carbs be needed?