BMW Boxer stuff

Originally Posted by Voltaire

um...i've had a few wines....but do you really want to change the stroke or make the engine narrower....? I'm thinking machined cylinders as opposed to shorter stroke as surely the capacity will be less...with bugger all compresssion...?
and yes Max...I'm motivated to do the R75/90/100s as....I might go for road legal cafe.....as I think I have a vin plate....
Go on Kickha start a boxer thread...make a change from Guzzler ones...
wanna buy a new bean can 336 cam...at cost? or an R65 crank....?

I was thinking of both narrower and changing the stroke, a R65 stroke at 61.5mm with 100mm pistons = 966cc, barrels and heads can be modified to get the compression to what is wanted

Bean can? pfffffft old tech, there will be a programmable ignition on this one, haven't decided on the cam yet but apparently Kelfords do a good one for them

Might be interested in the crank maybe, not really sure as I can't afford to do half the shit I'm planning anyway

Are you narrowing it coz you are scraping the heads, and having issues with ignition?

No, I haven't even got to the point of taking it to the track yet, that will be months away, I am just considering some options when it comes time to do the engine

I'm not having any ignition problems but I was going to replace the points anyway so for about 200 euro for a programmable ignition I consider that a pretty good option

Originally Posted by Kickaha

How big were the kits?

The kits took the R65 out to 850cc IIRC. For serious performance, the heads become the next bottleneck, because the R65 headers are only 36mm. It would probably be feasible to have the 336 cam-lobes copied onto an R65 cam, but it would be expensive and the results may not be all that spectacular.

If you can crack the code and figure out how to mix'n'match to achieve some useful performance, all power to ya. Many have tried, few if any have truly succeeded, all have been dogged by frustration and expense in roughly equal measures.

I explored a lot of options for a 500 BMW....one of them buying Toaster....then all the bits to make a parts Toaster.....there is a guy in Holland who races one with some success, JE pistons, custom frame......I gave up as it was a lot of time and money. Current plan is like Maxes to build up a bit o' fun track day/cafe bike.

What did they do with the Rob North BMW? I know it was a 750 but didn't that run a short stroke motor? or was it just shorter rods? to narrow it up

At the moment I'm working on my brakes and front end, the engine is a while away from being looked at, so I've ground off the rivets and detached the discs from the carriers, I'll get some 290mm discs made up and then I'll be looking for some Lockheed calipers to do a brake set up like the B & S bikes

Lester wheels anyone? http://www.trademe.co.nz/Trade-Me-Mo...-329939192.htm

You want to sign up to the Boxerworks US forum...theres not much there they don't know. What year is yours again...? pre 81?

1977 r100rs

I had a 78 R100RS. biggest improvement was later clutch/flywheel, Brembo brakes...mind you this probably had more to do with the master cylinder location and operation.
40 mm Dells. This gave a day night difference in pick up and responce. I fitted frame bracing but never really pushed it hard enough to notice.
I think yours has the larger valves than the later ones... The later forks are better in my opinion...not as soft, but you can braise up some of the damper holes...2 or 3...I think. I think the whole heavier oil/harder springs is not the way to go...better valving...Robert Taylor convinced me on the SS with a revalve.
I have a set of later fork lowers if you want to go Brembo... as I fitted the earlier lowers on to later uppers...as I want to retain the early 70's look.
...anyway back to Bevel pre ride checks.....out on a BFTP run this arvo.

Lightened flywheel, h/bar master cyl and braided lines, flat slides and 2 into 1 should be a good stage 1 upgrade. Max probably knows a thing or 2 for the forks, have tried progressive springs and they were good. Don't know if there are fork braces still around for these, I had a rude looking tube affair, worked well- looked fugly

I never had the $$ for fancy rear shocks back then and had to make do with Konis, anything these days apart from Konis would be better Works make a shock for them, wind down preload and adjustable air assist damping. Good feedback coming from that crowd and I like the set I have on a Guzz

Originally Posted by Voltaire

biggest improvement was later clutch/flywheel, Brembo brakes...mind you this probably had more to do with the master cylinder location and operation.

I am after a later clutch/flywheel set up, the brakes I intend to do the same as the B & S bikes with Lockheeds as that will still let me run NZCMRR events as pre76 and give me brakes that should be as good as the Brembos for pre82 as well

I just happened to be talking to a guy down here last Thursday who reckons he's got some 38 or 40mm Dellortos in his shed he might sell me

If you are into old boxers go to www.thevintagentblogspot.com for a selection of Rennsports and the R7 which used the same guards as my old R17

Sorry! That should read; www.thevintagent.blogspot.com with the fullstop in the middle.

I have been sorting out my Boxer Stuff.... finally found the frame I was looking for with a VIN plate on it. Its been deregistered in 2005 but its still on Carjam.
Is it as simple as bolting it together getting a letter from the Police saying " Sweet" and rocking up and getting it re registered?
Its a 1973 frame so only about 800 more sleeps till its cheap(er) rego