I’ve had an issue with my transmission for some time in that if I use the throttle in second, it feels like it skips a bit then continues to pull. If I baby it, it just pulls in the low rpms and then I shift to 3rd. Without cracking the case and having a person with more experience than I look at it, what may need replacing? What suggestions does anyone have on a path forward?
I’ve heard references to worn dogs & slots, needs for shims, etc. As it only happens in 2nd gear, and without having taken it apart (not that I’m likely the person to do that) I wonder if I should try to source parts like the M2,3 gear now before I find someone to take it apart?
Okay, so worn dogs. Stupid question: do all the gears on both the main and the counter shafts have dogs?
If I have this problem in only 2nd gear, is it likely that the main 2/3 gear needs to be replaced? Or is there likely a need to replace the main 4th or 5th which are adjacent to the M2/3?
On the same note, could the problem lie with the 1st, 2nd, or 3rd gear on the counter shaft? I don’t quite understand how it is all supposed to work together looking at the exploded parts view or the shop manual.
Some gears are splined on the shafts, some have dogs and some have slots that dogs engage with. Some also have dogs and slots. When you shift gears the gears slide on the shaft via force exerted to them from the shift forks. That’s bacically how the transmission of the power from the crankshaft gets to the front sprocket. I would tear the engine right down and look for wear on the dogs and slots. The dogs usually get the worst of it though.
So … how hard is it really to replace for example the M2/3 gear? Or any other parts that need replacing? I’m concerned that once I take everything apart that needs to come apart, I won’t be able to put it all back together. Or that I won’t have the requisite parts. I do happen to have an M2/3 gear. I’m not fully incompetent, how hard can it be? I ask myself, “What could go wrong?” Normally, I’d think to hire a professional, but I don’t have the sense that that is a good idea on such an old bike that matters more to me than to others. I’ve had it since 1986.
To get a better grasp of how this transmission works, I bought a used one on ebay for about $100 (price of a single NOS gear BTW). Interesting. So now that I understand how 2nd gear works, it would seem the right gears to have picked up without having looked at the transmission would have been C4 and possibly C2 since they are the ones that mate via dogs&slots. I guess I don’t need the M2/3 gear that I bought. For those who know about as much as I did, the M2/3 gear is splined and therefore can’t skip when the bike is in 2nd. Anyhow, looking at this “new” transmission, It doesn’t look obviously bad, but then I don’t really know what I’m looking at. I’m hoping when I get a look at my transmission this winter the damage will be obvious. The journey continues.
One thing to check would be the shift fork. if it wears slightly it wont fully engage the dog gear and cause The problem you describe. From memory the fork for 2nd also operates 3rd. if one side of the fork wears it can also allow the dog to float instead of positively engage.
On my F2 it happened on the 1st/4th Fork.
Chris,
if you do pull the motor down don`t follow the Clymer Manual steps for camshaft assembly and valve timing- it is totally wrong. Do a search of this forum for the correct proceedure, or get a copy of the Honda pdf from Forum.