1985 vf700f i need help

I have a 1985 VF700F and this is my hell... errrrm, I mean challenge:

Second gear used to stutter and disengage at about 4500 RPM. I brought the block to my mechanic who replaced the shift fork and the gear itself, and also the clutch because that was slipping. Now there is no longer the stutter, but second gear disengages at about 6000 RPM. He claimed that all tolerences matched up, and pulled it apart a second time to check.

His explanation was that after some research, he found that this V4's sometimes just wear so that part become dysfunctional.

Other mechanics have said that the problem might reside in the synchros (sp?) and that he may not have touched those.

What do I do? I really don't want to be mad at him, as he's a good friend of mine, but at the same time I want my forever bike to remain my forever bike.

Thanks,
A really confused Honda rider.

 

Please guys, I really need help!

 

Present that other mechanic's idea to your friend. If he gets mad at you, he will get over that and consider that option or discount it with his reasons. If he stays pissed...oh well. That's the best I can do cor you. I'm mechanically deprived.

 

Sounds like the dogs on second gear are worn. View attachment 27045 I'm not sure which gear is second in this diagram, but look at gear #12. The three dogs that mesh with the corresponding gear #7. If either the dogs or the holes that the mesh with are worn, then it can pop out of gear under acceleration. I'd take it to another reputable tech and have them tear it back down and have a look. Or get a factory repair manual and give it a go yourself.

 

Thanks for replying

When my mechanic split the block the second time, he said he checked everything transmission related to make sure the tolerances matched up, and they all did. Not sure if he might have missed something, but this guy is well known for restorations.

I guess my biggest question is does the engine wearing a certain way really explain the issue? Because logically it seems that if the engine had worn significantly, it would be happening to more than just one gear...

 

Also, after looking at that diagram, #12 was replaced, but could it be that something on gear #7 is worn so that the mesh isn't correct?

 

No, jumping out of gear is strictly a trans problem. Engine "wear" has nothing to do with it. You either have worn parts, or a bent shift fork. Jumping out of second is a common problem. And the three "dogs" you see on 12 mesh into the slots you see on 7. So it's possible the slots are worn.

Sent from my XT1080 using Tapatalk

 

I second dog clutch wear, if shift forks are confirmed not bent.

There are no syncros in the VFR transmission.

Motorcycles(most of them) have a constant-mesh transmission.

 

Jev said it already, the issue is going to be with the two gears is question. The shift drum , shift fork, shift shaft and the gears themselves need to be inspected. Something is oot of wack.

 

Thanks guys. Much appreciated. I can split the engine down to nothing, the only issue is putting everything back into place... Guess I'll have to find another mechanic.

On another note, I bought a 2013 CBR600RR, and I find myself wising to be back on my Interceptor.