Topic: CB550 Rough First Gear After Bike is Warmed Up

[kylenoland]

I've owned a '74 CB550 for a couple months now and have been tackling small issues on it and enjoying riding it nearly every day. The next issue on my list is to diagnose why the first gear is so rough once the bike is nice and warm.

When I first take the bike out, after letting it idle for a couple minutes after a cold start, first gear/friction zone feels normal. I can blip the throttle, let out some clutch and I'm off to the races. However, after riding for 30 minutes or so, taking off from a full stop is very rough. No amount of feathering the clutch matters. It feels like first gear sort of "catches" and clunks into place. It also takes a lot more throttle to keep the bike from stalling.

I should mention that the bike has a 4 to 1 Ton-Up exhaust installed by the previous owner. One of the first things I did after purchasing the bike was to have my local vintage Japanese shop properly jet the carbs for the aftermarket exhaust.

Any ideas where to start tracking this one down?

Thanks in advance!

[TwoTired]

How old is the clutch?  Miles?

Readjust clutch actuator linkage, and/or change oil types.    You could try Honda HP4 without Moly as a test process.  I personally favor a synthetic blend for air cooled motors, with its extended heat withstand properties.

FYI:
My 550s will start making shifting more difficult (clunky, more shift lever pressure needed) when it's time to change oil.  After oil change, it's back to shifting smoothly.  The change interval varies with the temps the motor is experiencing.

Cheers,