An Idea to fix my bike come on Guru's I need your help

[Motorhead]

If you don't know the story

Bike called Red now called FRed some where between 8,000mi to 25,000mi I noticed a MPG problem, I blamed on a 37/11 that got worse with a 32/11, Because my so called Rebuilt heads went bad from National city BMW machine shop

I wonder if this will work?

1980 R100S heads

with 38mm pipe fitments, will a 32mm carb work with a 44mm intake valve and 40mm exhaust

will even the 32mm carb fit?...... I'm sure I can streach the rubber adapter some

the motor is a R75/5 motor block with a 1974 R90 top end
312 cam

seeing these R100 heads are under 35,000 orginal miles, from a motor that was not rebuilt before what's the chance these will work?

And are they after the BMW cheese heads with valve seat problems that the BMW company said the casting place changed the metal mix?

[Major Softie]

Maybe.

You are just guessing now. That is an approach that can lead to a solution, but is, on average, likely to spend the most possible money in the search for that solution.

[ME 109]

It is difficult to part with a bike that has had so much work done to it, but...................
Why not buy an R100 with big valve heads and 40mm bings?

[Motorhead]

I spent a lot of Money on this bike, THIS will be my last BMW I will ever buy

some parts I bought were sent to me were wrong and when I send information of their mistake they say I lied

one box came from a seller with a 34/11, when I unpacked it was the 37/11, I pictured the part with the shipping box, they called me a Liar, no exchnage or offer to please me.

so I needed my bike to run and although the bike ran good, It was then I went on a long ride did I notice the MPG

I also got a pod from a seller with the wrong ratio and they pointed a the finger to me LOL

so more cheeters are coming into the BMW world.............

I figure the treatment of the dealer and ever other riders are the reason for the barn filling of these bike's no matter how well they feel and run

some parts came so worn out like Bing Carburators that didn't match the photo or working..... price of used part IS only treasue _IF_ it checks and works

I might go the same way as Matt did recently with his post of the 336 cam, most of the first low milage parts heads seem to be R65, They are smaller than a R75 or R80 head to which I would consider More right's than left's for R90

but since there is no other set like the big valves in Ebay I'm in a race for

So as far as most other motorcycle work I did in my past experence the Big valves seem like a good Idea as they are matched and unbroken parts Big valve work on Harleys and Triumphs and most other bike in my past......

the 32mm Mikuni should mix better and fuller

But as far full modfied BMW I'm in a area that more of less uncharted for me, maybe if I don't win maybe time to just part it out and go my own way and leave

Its not Like BMW will ever revive the Airhead and it will be priced far beyond what I think they are really worth

My Harley will go the distance I'm sure of that.............

[Chuey]

some parts came so worn out like Bing Carburators that didn't match the photo or working..... price of used part IS only treasue _IF_ it checks and works

Lyman, that's how I feel about the lower end I bought from you. Then you acted like you didn't know me when I called a couple years later and identified myself as "Chuey on Boxerworks" and by my real name, and told you I was the guy who bought the lower end from you. Since I was at your house talking with you for over an hour, I was disappointed at how you wouldn't acknowledge knowing me on the phone. The lower end is in such bad shape that I'm afraid to use it. If you need it, you can have it back. Not a huge deal, but it told me lots about you and makes your posts more interesting. I think this may be a case of what goes around, comes around.

Chuey

[Motorhead]

Sorry Chuey
poor mic's and speakers are really problematic with me and the phone it self, I never found peace in useing it..... its like someting missing

I always like face to face

what was the trouble with the crank?

I actually enjoyed your vist, but I seldom have vists

and what do you mean that told you a lot about me?

I'm not top of the food chain

I don't need/want anything back, But if I can't find a way to get my ole BMW up, could be time to move on...

after the accident I could never restore it.... even the insurance Low balled it, even said nothing was wrong with it
many Non BMW motorcycle events didn't know what it was.......

the produced Ebay and other places of replacement was not enough proof

you suggest its a cycle of events that brought me here to this point? so to say I'm a bad person?

Have I gone too far?

IS German engineering worth it?

its just a bike....... metal, plastic and etc. anything thats added to ownership is self inflicted

my first BMW was 12 years old, I covered 89,000 before I rebuild that one and I owed 3 years, my second is about 39 years old now,it covered 87,000 to a valve recession.... in 39 years most BMW's have covered a lot of miles
some parts came to the 3dr over size so first size parts becomes farther and harder to come by......

I seldom can afford the hard new parts like Nicsil jugs or the 336 cam so used parts is my usual habit, all the mods were used parts

So I don't know what to say or do Chuey

Lyman

[Chuey]

I'm saying that if you describe something in glowing terms and it does not measure up, well, that's what you seem to be complaining about. That's what I mean by "goes around/comes around".

Chuey

[Duane Ausherman]

Motorhead said, "I spent a lot of Money on this bike, THIS will be my last BMW I will ever buy"

I second that idea.

[mattcfish]

If you don't know the story

Bike called Red now called FRed some where between 8,000mi to 25,000mi I noticed a MPG problem, I blamed on a 37/11 that got worse with a 32/11, Because my so called Rebuilt heads went bad from National city BMW machine shop

I wonder if this will work?

1980 R100S heads

with 38mm pipe fitments, will a 32mm carb work with a 44mm intake valve and 40mm exhaust

will even the 32mm carb fit?...... I'm sure I can streach the rubber adapter some

the motor is a R75/5 motor block with a 1974 R90 top end
312 cam

seeing these R100 heads are under 35,000 orginal miles, from a motor that was not rebuilt before what's the chance these will work?

And are they after the BMW cheese heads with valve seat problems that the BMW company said the casting place changed the metal mix?

R100 heads won't fit right on your R75/90. The squish band would extend past the tops of the barrels creating a not so efficient cumbustion chamber. You might even suck more gas. You'd also loose some compression. If your bike is getting poor mpg I'd say compression is something you don't want to loose. You'd need to machine up some kind of adapters to get 32mm carbs to fit on 40 mm spigots. Adapter are available to fit 38mm Dellorto's to 40mm spigots. You may be able to get those and have them machined down. Again the flow would not be very efficient, some say smaller 40mm intake valves actually work better with cams because they keep the mixture velocity higher. You're much better off with R90 heads. If the problem is with the heads then get the problem fixed. Not a whole new head job, have someone who knows their stuff pinpoint the problem and correct it (if Nat'l City hasn't guaranteed them). It's all cheaper than another bike, that's my philosophy.

[Motorhead]

Thanks Matt

I read this before my evening relaxing time

I wondered if my price would carry me to the end.............. I began to think how to go if I won

I can sell some stuff rethink my idea as one BMW spec I haven't tried, I have time! as I have another bike to ride thats working out well .....

Slow down a little............. I don't mind working on it, IF the work I do goes as planed and lasts in some timely fashion

PHEW!.............. I lost them this Morining so.......... 900cc it will stay

there is a shop un Upland I found that has a good record and I'll get me wife to call and speak to them maybe answer my questions

and get them rebuilt