Are the 1985 cams or the "European" cams truly different than other K100 cams? If so, can anyone furnish actual numbers such as lift, duration, timing? Are they a different part number?

i believe the california and possibly the swiss cams may be different, from posts in here .

there were lots of aftermarket products (now scarce ) available .

you might try using the "search" feature dewey

i seem to recall a post about the cam durations a little while ago ,,,

240 degrees from .050 lift was pretty standard (265 deg ?) for most high performance twin cams of the era, no point in going much further for "on road rideability "

i guess the theory was more bangs per rear wheel revs produced good torque from 3k up ...and all those engines reved so well, including our mighty " k "

found this, but doesnt answer the question about differences though

http://k100rt.aforumfree.com/t3568-modifying-the-cam-timing

Friend of mine drove K 1986 engine for swiss market with RPM limit at 6500. Even the red line mark on instrument was at 6500. To get full RPMs and power he changed black box (probably fuel injection controller) under the tank and engine started rev full range to 8600 RPM. Anybody knows for shure was it the only difference between swiss K and european K? Maybe camshafts?

Regards

I believe the only difference on the cams were between the 85 and 86 model. The 85 has 10 more HP.

The Swiss version had a rev limiter. They used the original rev limiter bulit into the fuel injection computer, but changed the setting to cut the injection at 6,500 rpm.

Well, I think that I have found the definitive answer to this question and that is this:

According to specs from a German, UK and US factory service manual and cross-checked with the Haynes manual and BMW part numbers, ALL K100 2V cams are the same EXCEPT for California bikes. It seems that the difference is that worldwide and 49-state bikes got cams with 284 degrees duration and CA bikes got cams with 256 degrees duration. BMW lists the standard cams and CA cams.
The advertised horsepower for ALL year 2V K100 engines is 90. It appears that the myth of the 85 cams or the "European" cams being "hotter" is just a myth.

I have a set of 85 cams here if you want to compare.

Rjtrucker wrote:I have a set of 85 cams here if you want to compare.

PM'd you.

Have a look at post #10, about the same subject.

Inge K. wrote:Have a look at post #10, about the same subject.

If that is the case then ALL US 2V bikes have "California" cams, correct?

Dewey V wrote:If that is the case then ALL US 2V bikes have "California" cams, correct?

I think this statement is correct, but in Canada we have a lot of K100 European style.
Checking your VIN # on this site should tell you if you have a US or EU model.

CF

Hi Guys, I'm new here but I have done a lot of research on this subject , and found most of my informations on cams on the vintage mini cooper web sites(these guys use K100 2an4 valve and K11and12 heads on there mini's to get more power out of them). As far as I could determine in 85 the European and 49 state bikes had the hotter cams(284 duration and higher lift) in 86 all U.S. bikes received the smaller cams that the California bikes have, I think because of tightening emission controls in the U.S. The K100 4v suffered the same fate with the Euro bikes getting the hotter cams and the U.S. getting the smaller cams. The K1100 all received the smaller cams do to a 100 hp limit Europe, the K12 RS and GT all have the hot cams and biggest throttle bodies(38mm). I installed the hotter cams and throttle bodies and fuel rail(3.5 bar regulator instead of 2.5 on earlier bikes) from a K12RS on my 96 K11RS along with a Ramus exhaust and a tweak to the motronic 2.2 and the the power difference put a real big permanent grin on my face. The engine revs up so fast in 1st and 2nd gear that the engine beats the tach to the rev limiter.

Interesting thread.
Any info on pre 85 cams? Are the earlier ones different again?
My 84 K100 feels perkier than my 89 one did, but then imagination is a wonderful thing.
Maybe it's just a 'tighter' engine.

GWK11RS wrote:Hi Guys, I'm new here but I have done a lot of research on this subject , and found most of my informations on cams on the vintage mini cooper web sites(these guys use K100 2an4 valve and K11and12 heads on there mini's to get more power out of them). As far as I could determine in 85 the European and 49 state bikes had the hotter cams(284 duration and higher lift) in 86 all U.S. bikes received the smaller cams that the California bikes have, I think because of tightening emission controls in the U.S. The K100 4v suffered the same fate with the Euro bikes getting the hotter cams and the U.S. getting the smaller cams. The K1100 all received the smaller cams do to a 100 hp limit Europe, the K12 RS and GT all have the hot cams and biggest throttle bodies(38mm). I installed the hotter cams and throttle bodies and fuel rail(3.5 bar regulator instead of 2.5 on earlier bikes) from a K12RS on my 96 K11RS along with a Ramus exhaust and a tweak to the motronic 2.2 and the the power difference put a real big permanent grin on my face. The engine revs up so fast in 1st and 2nd gear that the engine beats the tach to the rev limiter.

Thanks for the info. I guess I didn't have it figured after all.

BMW sold a few K100 and K100RSs in the US in late 1984 as early release 1985 models. They were 49 state only bikes not legal for sale in California. They had the US required lights and reflectors, but were otherwise pure Euro-spec machines with no evaporative emissions equipment, the push button style gas cap with a big wide easy to use opening and no flap to fight, and most importantly the same 284 degree cams sold on K100s everywhere else in the world (except maybe Switzerland, but I don't know enough yet to say yea or nay).

Around April of 1985 BMW began selling a 50 state legal bike in the US (note: there was never a "California" model as such). These came with 256 degree cams, costing 7 horses and taking away some of the original top end rush. They also had a miserable gas cap with a narrow opening and a flap supposedly to minimize evaporative emissions. They also vented the gas tank into the engine through a check valve so you couldn't (supposedly) send raw gas into the crank case) and to prevent crank case pressure from pressurizing the tank. It could suck fumes from the tank but not blow back into the tank. Says right here in fine print!

Today, if you want to buy replacement cams from BMW for the K100, 284 degree cams is all they offer.

Correct on the K100 16V and K1100 cams. I have oft wondered what a K1100 with Euro spec K100 16V cams would be like. Now I have an idea. Helluva bike I bet.

This says it all...!