I have a maintenance question which I have asked many people and have not been able to get a good response to, so here it is:
I have a 1996 1100 BMW GS. It hesitates when I give it throttle. This started only when I put the motor under a lot of stress, I.E. opening it up from 80 to 90 with two people on and sidebags to add to the wind drag. Now it does it all the time. I can’t even get past two miles an hour unless I gently give it the most miniscule amount of gas. It took about a month to get to this point.
I thought I needed to gap the valves, so I did that, and it worked, for about 600 miles. Now I am back where I started. The bike has been sitting now more than a year.
This all started within a few thousand miles of me giving the bike a major service. I rode this bike to Panama, with someone on the back and also on many dirt roads, which needless to say did a lot of damage. I continued driving it for about a year after I returned from the trip, until the master cylinder started leaking brake fluid on my hand. I changed that, replaced the right side head gasket which was leaking, replaced the air box which was broken(maybe something got into the fuel injectors before I did the replacement), and quite a bit of other things which should be unrelated, (a little electrical work, etc.). Like I said the bike ran well for about 1-2 thousand miles after this service.
What could this be? I can’t keep gapping the valves every 600 miles. Any Ideas?