39 transmission

[49 pan]

Could someone that is riding a 39 knuck tell me if its is normal for the transmission to grind when shifting from 1st to second,

Thanks

[Jerry Wieland]

Yes they are a bit prone to that. If your clutch drags at all that is what happens. More prone to grinding on the downshifts. Just make sure your clutch is in prime shape and the linkages are adjusted properly.

Jerry

[Chris Haynes]

The '39 was a sliding gear transmission. Thus the grind. All others were constant mesh so no grinding.

[49 pan]

Thanks for the replies, Jerry and Chris.


Because it is a sliding gear transmission,would 3rd and 4th also have that tendency? I have cleaned and adjusted the clutch ,adjusted the linkage and it is somewhat better but it still grinds tooooo much going into 2nd , all other gears seem to work normal.

Thanks
Dick

[Rubone]

3rd and 4th are constant mesh, only 1st and second are sliding type. Only 1st gear actually moves when shifting. It will usually clunk into second but grind when engaging 1st or on downshifts.

[49 pan]

Robbie ,

thank you very much

Dick

[enthusiast]

Dick, yes it is the same on my 39, and it is freshly redone - everything as the others described it. A horrible transmission - but we love it so because its original... I am just an

enthusiast

[49 pan]

enthusiast, thanks for your reply

I am going to work a little more on the clutch,

Dick

[Carl Olsen]

I have a 39 with almost 50,000 miles on it since I restored it, I have our prototype gear set that we had Andrews Products make for us that has improved shifting dogs and ramps plus a special belt drive from BDL that gears the primary drive up for cruising at 65-70 MPH that you can run the stock 22 tooth trans sprocket for accurate speedo reading, plus a modified Competitor clutch that disengages better than the original. It works fantastic, but I still have to double clutch it going from 3rd to 2nd and 2nd to 1st for smoother engagement.
Carl

[49 pan]

Thanks for your reply Carl

I will see how much I ride the bike before making that kind of investment over $2000 I am sure. I will try to make it livable for now by working on the clutch release.

Dick

[rousseau]

Dick
A properly working clutch is key to shifting any transmission. But as Carl said, you must learn to "double clutch" when down shifting this type of tranny.

[49 pan]

Rousseau
Thank you for the response

I am rebuilding the clutch at this time, we will go from there.

Dick

[enthusiast]

folks,
what is the meaning of "double clutch"? ... to pedal the the clutch rocker twice just one after another? (I never did that...)
What should be the technical reason for that doing, what should happen inside the clutch or inside the transmission doing this? I canīt see anything but spending some time to allow the engine to rev down and reducing the speed of the bike - which both will help for quite gear shifting? (...that way I do it).
Thanks for any explanation.

enthusiast

[bobphd]

I have no experience with the 39 sliding gear transmission. My very late 39EL has the regular transmission gears. I beliieve it may have come like this because it is so late but no one knows for sure. I have been riding hand shifters for almost 40 years now and very seldom ever use the clutch for shifting gears, only for starting from a dead stop. They "float" quite nicely and smoothly, both up and down if engine,transmission and wheel speeds are close. It is not a fast way of shifting but who is in a hurry? Way back when in the days of jockey shifters mounted to the shifter lid you really had a feel for the transmission and this made shifting without the clutch very easy but is still no problem with tank mounted shifters. Ratchet lid shifters are a different story and I almost always clutch when shifting these.

Bob

[D.A.Bagin]

My 440 has a similar set-up. What I do is try to match the rpm of the motor to the trans and slowly transition the gear change. Shift from 1st to neutral, release the clutch, wait a bit to let the rpms drop, push the clutch back in and then ease the shifter into 2nd with little or no grinding. 2nd to 3rd is no problem, clunk, and it goes in. Kinda like clutchless shifting of an over the road diesel truck. Just like what Bobphd says. Seems to have worked for me.