My '75 R75/6 has been running "rough" as of late. Not being mechanically inclined, I thought I would come here in hopes of getting a clue of what to look for.
Over the last few months I noticed the bike would falter/run roughly on rare ocassion as I was accelerating around 4500-5000 rpm. It would only be a 1-2 second hesitation and then the bike seemed to run fine from then on.
The last couple of days I've noticed these same symptoms appearing more frequently, and have noticed the engine producing a different, muffled-like sound, which seems to be coming from the front of the bike. I only notice this sound when manipulating the throttle and/or when at higher rpm's and I release the throttle to slow down.
I noticed yesterday that my throttle cable connection was very loose on one of my carburators. After tightening the cable, the bike is running smoother, although the bike still has this muffled sound to it.
The bike idles fine, so I'm assuming (maybe incorrectly) that the carbs are synchronized. I plan to check this later tonight. I did notice some cracking at the end of one of the plastic tubes that runs from my right carburator to the air box and plan to order a new one today. Thought this may be the cause as well?
I am unfamiliar with the points and how to or how often they need to be adjusted. It's been awhile since I had that done (40,000 miles or thereabout) and wondered if this may be my problem as well.
Any feedback would be appreciated.