Downshifting - impossibru
#1
Downshifting - impossibru
Looking for more advice.
I'm still running stock 6 speed with a 5X shifter rebuild kit. Finding it really hard to downshift when I'm going hard under brakes, I'll bring the revs up to match the downshift, but I really struggle to engage the gear. When going slower / less rpm there is no issue at all.
I've experienced this with last two 6 speeds I've had, I damaged the synchro on the previous box as I forced it in under pressure 🤦🏻-♀️
I'm still running stock 6 speed with a 5X shifter rebuild kit. Finding it really hard to downshift when I'm going hard under brakes, I'll bring the revs up to match the downshift, but I really struggle to engage the gear. When going slower / less rpm there is no issue at all.
I've experienced this with last two 6 speeds I've had, I damaged the synchro on the previous box as I forced it in under pressure 🤦🏻-♀️
#9
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What power are you making? I partially separated 4th gear, which is a pressed together gear and it became hard to shift into many gears but that was at all speeds and up shifting and downshifting both.
I'm going to guess it's fluid related since it happens at higher RPMs and more often on downshifting. If the oil is too slick the synchros won't have enough drag to match gear speeds quickly to allow engagement.
I'm going to guess it's fluid related since it happens at higher RPMs and more often on downshifting. If the oil is too slick the synchros won't have enough drag to match gear speeds quickly to allow engagement.
#11
Im not sure if related but change fluid is a good test if it is this. Being Motul I wonder if it is similar....
Our MX team used to use the high end Motul Motorcycle gearbox oil (I forget the name now Pro or expert somethign liek that...) in the National champs one year and we all suffered missed shifts, jumping out of gear issues. Scarey on a motocross track.
It was only when I had used up my stock of sponsored supply and used the standard gearbox oil for a practice session that it suddenly fixed the problem. We were all blaming that years team Honda Crf450's as being a poor design until then.
The high end Motul oil was just to slippery for the synchros. As soon as everyone changed back to the standard stuff everyone was happy again.
Our MX team used to use the high end Motul Motorcycle gearbox oil (I forget the name now Pro or expert somethign liek that...) in the National champs one year and we all suffered missed shifts, jumping out of gear issues. Scarey on a motocross track.
It was only when I had used up my stock of sponsored supply and used the standard gearbox oil for a practice session that it suddenly fixed the problem. We were all blaming that years team Honda Crf450's as being a poor design until then.
The high end Motul oil was just to slippery for the synchros. As soon as everyone changed back to the standard stuff everyone was happy again.
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