R100RT Transmission - 4th Gear Failing to Engage

[bhightower]

At this date I have changed the transmission fluid to Synthetic (Amsoil Severe Gear 20W50 Motorcycle Oil) as some suggested. Here are my most recent findings. I can confirm that it is a 5 speed gear box and the miss occurs on shifting gear 4 and 5, so the Dogs are seemingly the problem, as described above. There continues to be a slight, very slight play in the shifter, but a BMW dealer familiar with Airheads said this is common; Others would probably not notice this as it is so small. I probably also need a clutch cable. But with that as a context, here is what I have found since the change. The synthetic gear oil has helped accuracy in shifting. I would say it is 30% better. When I employ a pre-load on the shifter before engaging the clutch, it improves to a 60% improvement. I'm pleased with this as a result. It is an old bike (1982), with only 20k miles, I will consider this a successful treatment. I rode Honda's before this, and my experience with the gear box shifting was exceptional. I have adjusted and the bike has adjusted.

Many thanks for all your help out there in motorcycle-land! Cheers!