Odd 1st gear issue

[norcal rider]

Hello all. Wasn't sure how to word the subject line, but here's the 1st gear issue. Bike is a 2003 with 47K on the clock.
When coming home from a ride I sometimes like to coast the bike in neutral into the driveway. Kinda fun. Normal street to driveway transition. A couple times when I hit the transition from street to driveway, in neutral, the bike shifted by itself into first gear. The first time it happened I nearly ran into the garage door. Just in time I pulled in the clutch lever and hit the brakes. Second time, still a surprise, but I was curious if it would happen again and was ready. Sure enough, hit the driveway and the bike shifted by itself from neutral into first gear. Has only happened twice out of the many times I've done this, but what the heck? Why would this happen? And no, my foot did not hit the shift lever.
Any ideas?
Jay

 

[Dan Cooper]

Hello all. Wasn't sure how to word the subject line, but here's the 1st gear issue. Bike is a 2003 with 47K on the clock.
When coming home from a ride I sometimes like to coast the bike in neutral into the driveway. Kinda fun. Normal street to driveway transition. A couple times when I hit the transition from street to driveway, in neutral, the bike shifted by itself into first gear. The first time it happened I nearly ran into the garage door. Just in time I pulled in the clutch lever and hit the brakes. Second time, still a surprise, but I was curious if it would happen again and was ready. Sure enough, hit the driveway and the bike shifted by itself from neutral into first gear. Has only happened twice out of the many times I've done this, but what the heck? Why would this happen? And no, my foot did not hit the shift lever.
Any ideas?
Jay

Just what kind of responses are you expecting that won't offend you???

dan

 

[Bounce]

My recommendation is also the least expensive to implement. Don't coast in N.

 

[RossKean]

My recommendation is also the least expensive to implement. Don't coast in N.

Agree, but it shouldn't do that.
I would first of all have a look at the shift linkage to make sure that it is moving easily. It is a good idea to take it apart annually and clean/lubricate moving parts.
I would then look at the parts fiche for the shift shaft and make sure that the springs are properly connected and not broken or weak.

https://www.partzilla.com/catalog/yamaha/motorcycle/2004/fjr1300-fjr1300sc/shift-shaft

Does the shift lever positively ratchet back to the center position after a shift?

 

[Coachpilot]

Check shift detent spring... and you don't have tosplit the cases for that one.

 

[norcal rider]

Agree, but it shouldn't do that.
I would first of all have a look at the shift linkage to make sure that it is moving easily. It is a good idea to take it apart annually and clean/lubricate moving parts.
I would then look at the parts fiche for the shift shaft and make sure that the springs are properly connected and not broken or weak.

https://www.partzilla.com/catalog/yamaha/motorcycle/2004/fjr1300-fjr1300sc/shift-shaft

Does the shift lever positively ratchet back to the center position after a shift?

I've serviced the linkage at least twice since I've owned the bike. Everything is working fine. Thanks for the suggestions.

 

[norcal rider]

Check shift detent spring... and you don't have tosplit the cases for that one.

Thank you for the suggestion.

 

[wfooshee]

That detent spring comes to mind for me, too. if it's a bit weak, the shift drum can maybe roll out of neutral if it takes a jostle. That neutral notch is WAY smaller than the notches between gears!

You'll need to remove the clutch basket to really see it, which brings its own set of problems with reinstalling the basket correctly, as it drives one of the balancers which you do NOT want to get out of time, and it has to line up with dogs at the back of the basket, on a sprocket that drive the oil pump.

 

[norcal rider]

That detent spring comes to mind for me, too. if it's a bit weak, the shift drum can maybe roll out of neutral if it takes a jostle. That neutral notch is WAY smaller than the notches between gears!

You'll need to remove the clutch basket to really see it, which brings its own set of problems with reinstalling the basket correctly, as it drives one of the balancers which you do NOT want to get out of time, and it has to line up with dogs at the back of the basket, on a sprocket that drive the oil pump.

Oh boy. Thanks for taking the time to explain. Normally I would be all over it, but I have to sell the bike due a spinal issue, so not willing to dive into this. It's not that big of a deal and has only happened twice in 9 years of owning the bike. Wow, hard to believe I've had this bike for 9 years!