R850R sometimes running on 1 leg

[JohanOtten]

Hello people. So I almost completely had my bike apart and together again. I really wanted a bmw and I really didn't want a GS1100 with the beak and was low on money. Oh and I'm 6'8" so I converted a 100k r850r with gs suspention and footrestplates to an awesome handling and driving bike that is insanely high (I can't mount it easily when i have to many layers on) and just good for me, what an awesome bike it is!

There is only 1 thing that remains. Then the bike is cold and you pull open the throttle the acceleration isn't linear, he someimes seem to miss a beat. Also I when it's wet weather and a start it he seems to run on one leg only, when it warms up its gone. I had it stand in the rain without cover for a few hours once and then the problem was really bad. So the sprakplugcables touch the A-arm and are a bit dented there so I made an extra piece of tube around it for insulation. Bt the problem remain. Could it be something else then the spark plug cables? Or should I just replace them?

[joelh]

I'm betting on spark plug cables. That would be the easiest and most likely candidate. Not sure that will help your cold acceleration problem though.

[philbytx]

One wet weather issue is definitely your HES wiring, which is under the alternator belt and is a known fault on early oilheads. The covering of the wiring disintegrates and can short out causing timing problems. Plus, as someone else said, your plug wiring or plugs could also be an issue.

[Duc750]

Can you post some pics with the GS footrest plates on ? - I guess you are also using GS stands.

My 850 aslo has GS suspension on it now and I've had to lengthen stands but the logical solution may be GS footrest plates. Did you also change the paralever arm for a GS one ?

Regarding the original question. if you've checked that the rh throttle body cable can't be un seated by anything then my guess would be plug wires too or maybe the LT connection to the coils as water could get in there.

Its one of those annoying and time consuming but cheap problems to fix

[JohanOtten]

I'll make some pics when he weather gets better here. I have GS footplates and GS middle and side standard. I didn't change the A-arm, I thought these were the same, but is the GS's actually shorter?

Thanks for all the advise, I'll have a look at all that (If I can translate and find it) and see if I can find the problem.

[Duc750]

The A arm is the same but the paralever arm from the gearbox to the final drive is shorter. Its a commoin mod on the r1100s.

[JohanOtten]

oops, read it wrong, yeah I changed that too.

[omg1010]

Johan, the paralever arm of the GS is shorter (if I remember well by 15 mm). I had mounted the same on my R1100R and it lead to slight elevation of the rear and a slightly more agile riding.

I can only recommend changing the paralever arm.

Brgds
Oliver

[JohanOtten]

Thanks Oliver, I misread the post or just wasn't there when I reply'd. That was one of the first things I changed was the paralever arm. I tried to put some pictures here from picasa but it didn't work and the new windscreen and paintjob are almost done now, so when he's all happy and finished I'll post the pics.

Motor ran bad the first 10 minutes again today, during a stop I also noticed the right cilinder isn't hot at all (comapred to the left one) the ignition definately seems to be the problem. I ordered some good 2nd hand cables too see if that is the problem and I'll get a new sparkplug to test that aswell. If all that fails I'll be back

[omg1010]

Hi Johan,

why don't you check the ignition of the cylinder in question by removing the spark plug, put it in the plug and then onto the cylinder so the spark plug has ground. Ignition on and turn the engine. You can then see if there is a spark or not ...

Brgds
Oliver

[JohanOtten]

Hej Oli, thanks for the tip. I allready made sure it wasnt sparking, but it was hard to see because it sometimes works and sometimes doesnt. I just removed the bobine and unplugged the sparkplugcables there and it was quite corroded. Cleaned it, but wasn't really consent with the way they looked so put a nice pair of 2nd hands on there and everything works great now. Even when it's cold its just pull the (semi)choke and run. Very happy. Putting the last layers on the new paintwork too! (I hoot up with the clear coat so had to do the whole thing again)

[JohanOtten]

Hej Oli, thanks for the tip. I allready made sure it wasnt sparking, but it was hard to see because it sometimes works and sometimes doesnt. I just removed the bobine and unplugged the sparkplugcables there and it was quite corroded. Cleaned it, but wasn't really consent with the way they looked so put a nice pair of 2nd hands on there and everything works great now. Even when it's cold its just pull the (semi)choke and run. Very happy. Putting the last layers on the new paintwork too! (I hoot up with the clear coat so had to do the whole thing again)