Power Kit for an R75/5

[Garnet]

Just for curiosity sake, what top speed could be feasible with the new Kit, and
Horsepower rating?

About 50 plus

I hope that wasn't the answer to his first question . . .

No, he ment the age of the members here.

[mattcfish]

Just for curiosity sake, what top speed could be feasible with the new Kit, and
Horsepower rating?

Not sure how much you'll lose with the R75 valves. My R90 with 42 intakes and 40 exhaust would do over 114mph (unfaired) with 38mm Dellorto carbs. With the power kit and the sport cam I'm almost afraid to find out.

[Garnet]

Just for curiosity sake, what top speed could be feasible with the new Kit, and
Horsepower rating?

Too mant vairables to say for sure, but I would think that somehwere around 15% power increase on a 750 can be expected. As for top speed that is even harder to predict.

[boxertwinjeff]

Just a note, I ordered one of these kits on the 16th and it arrived yesterday! My '73 is going to be soooo happy!

Mine took around the same time to arrive in Australia,
Unfortunately, I gotta fly out to my job for 3 weeks on Tuesday, no test riding until I'm back,
so i'ts gonna be the longest 3 weeks ever!

[boxertwinjeff]

Just got word from my Mechanic, the new Engines' running sweet!,... but it appears
theres way too much power for the Clutch to handle,. now it's slipping.
Where do we go with the Clutch situation now? thought I'd ask you guys before
I talk to my Mechanic tomorrow.

[Deleted User 72]

Just got word from my Mechanic, the new Engines' running sweet!,... but it appears
theres way too much power for the Clutch to handle,. now it's slipping.
Where do we go with the Clutch situation now? thought I'd ask you guys before
I talk to my Mechanic tomorrow.

I've got the same issue. Clutch slipping. I'd call it a problem, but the extra power is too much fun.

So, here's hoping you get a good answer.

[chasbmw]

I also suffered clutch slip on my 1070 kitted bike. The bike already had the stiffer BMW clutch spring, so I fitted a HPN friction plate, it was very expensive and is fitted with an K75 spring.

Part of me thinks that the clutch slip might have been due to too Mitch grease on the splines and putting some grease on the clutch splines?

Charles

[mattcfish]

I also suffered clutch slip on my 1070 kitted bike. The bike already had the stiffer BMW clutch spring, so I fitted a HPN friction plate, it was very expensive and is fitted with an K75 spring.

Part of me thinks that the clutch slip might have been due to too Mitch grease on the splines and putting some grease on the clutch splines?

Charles

I put a post 81 tranny, clutch, and 9 tooth starter on mine. Absolutely no slip with a very powerful motor. Very nice revs with the almost non- existent flywheel and the clutch is so easy to pull. You can use the pre 81 clutch and tranny, but you need to make sure it's not very warn and you may want to have the pressure plate surface hardened. On eBay the tranny, clutch and starter cost me less than $300 and they all had much lower miles than my 1975 set up. Aside from being much lighter the later style clutch is designed to handle the torque. New components for just the old style clutch will cost you much more.
If you are just bumping up the cc's the old style clutch should be fine. It's what they used on R100's up until 1980. When you go with a sport cam, performance carbs, and improved breathing then you'll probably want to make changes to the clutch at some point.

[boxertwinjeff]

Hey Matt, Are you saying I could get away with JUST an updated Post '81 Clutch, and nothing more,
seeing shes had no mods to the Cam and the Carbs are still the stock Bings?

[Indian]

I will be ordering my Vössner forged pistons for my R90S this Winter, if i just dont ride south to them and have it fitted straight away.....I will be in Holland for a meet this fall and Motoren Israel are only a few hours away.