1973 750 Commando, transmission bug

GUTS · Sep 22, 2015

Hi fellas, it's been a while since you helped me get the '73 Commando running last year and I still appreciate it. The bike is still running great, the engine never skips a beat and it's a blast to ride. Lately the transmission has been hard to shift, especially from first to second. You have to shift twice, once to get it from first to neutral and again a little harder to get from neutral to second. The transmission oil level is good and the clutch still feels like it always did, great. What could the shift problem be? I would like to have a better idea before I start taking things apart.

1up3down · Sep 22, 2015

guess is the clutch plates are not separating enough to allow smooth shifts

the plates could be fouled with oil from the primary and are sticking together

I would take the outer primary cover off and using your handy clutch spring depressor remove and clean all the plates

OR it could be as simple as your clutch cable has stretched and needs adjustment at the lever or possibly at the clutch primary adjustment

Torontonian · Sep 22, 2015

First to second ,pull the outer cover , replace shifter hair - spring , remove inner cover ,replace 1 ST. gear bush . Very delicate.

Brly · Sep 23, 2015

I would bet the clutch plates are stuck together as 1up3down suggests. Easy to clean them up.
It has been suggested that the clutch plates should be cleaned at the beginning of every riding season. I have found this to be good advice.
You won't believe how easy it will shift once they're clean and separating properly. Shifting will get more difficult as the plates begin to foul again.

Ben

jimbo · Sep 23, 2015

Torontonian said:
First to second ,pull the outer cover , replace shifter hair - spring , remove inner cover ,replace 1 ST. gear bush . Very delicate.

+ 1

GUTS · Sep 23, 2015

Thank you very much my friends, I will press on with the new information.

Torontonian · Sep 23, 2015

Hey whilst you are in there , don't forget the roller layshaft bearing switcharoo.

batrider · Sep 24, 2015

Part of the gearchange ratchet is above the oil level and may have rusted. I've found some really crusty ones. When you pull the outer cover it's all right there. Usually if it is a clutch plate sticking problem you will have trouble finding neutral and keep going past it into first or second.

Russ

milfordite · Sep 24, 2015

Check the above, but it could also be a tight primary chain. Easiest thing to check!

fiatfan · Sep 24, 2015

This is how my return spring looked like ( the left one :mrgreen: ), the stop plate was also pitted with rust, but still ok. Haven´t driven the bike since I replaced the spring, but dry-testing by spinning the rear wheel and change gears, it feels much better.

Tommy

Torontonian · Sep 24, 2015

Once those springs get all rusty , their strength is compromised. The product Shockproof gear oil seems to coat everything and it clings very well to the shifter mechanism , preventing the rustages. :wink:

ashman · Sep 24, 2015

Moisture in the gearbox is always a problem and thats one of the reasons for rust, mostly if the bike isn't used that much, I alway change my gear box oil yearly without failure even when its doesn't need it, gear oil is cheap.

Ashley