Reverse won't engage unless no resistance on drive line

[Flipper]

Out riding today and I am getting code sd-08 when I attempt to shift into reverse. When I got home put it in my shop and took a look.

Took the actuator off, it is working fine as it rotates back and forth when engaging/disengaging reverse. Pulled out the extension gear and nothing obviously wrong there.

Put it back together and still no joy, code sd-08 when attempting reverse. Put it up my stand and it shifts back and forth just fine with no resistance on the drive line.

I have an extended warranty so it's going back to the dealer as I assume something is wearing in the chain case.

Any thoughts before I haul it back?

 

[lakercr]

Changed belts lately? Not enough deflection will put a load on the chain at idle.

 

[Flipper]

It has been a couple 1000 km's now that you mention it and I did not check my belt when I was troubleshooting. I'll try that in the morning and let you know how it goes. Thanks for the suggestion, I should have thought of that.

 

[lakercr]

What I meant was that if you'd put on a new belt lately, you might not have enough deflection; assuming it was good on the old belt. Regardless, deflection is something that should be checked as part of your diagnostics. If you've had the secondary off and mixed up the offset washer stack you could create this issue. Are you using an aftermarket adjuster, or stock?

 

[Flipper]

I am running stock secondary and have not have it off the sled. I do have the BoP adjuster on my bench waiting for me to install.

Went out to the shop this morning. I tried an old belt (33mm width), a new belt and no belt. The only way I could get a shift to reverse to work with the sled sitting on the floor is without any belt.

 

[jonlafon1]

Is the actuator on correctly. I know it is obvious how it goes on. But I could see some turning it the wrong direction so to speak when lining up bolt holes. Not even sure this would cause your issue? When putting back on the whole thing gets turned counter clockwise slightly. So it goes on and is cocked slightly to the right then turned slightly back or counterclockwise direction until three bolts line up. Make sense?

 

[cannondale27]

Its possible the actuator just doesnt have enough strength to do the job. Grab onto the gear on it with a pliers and see if its weak when button is hit. If so guys have had good luck popping the motor out and cleaning the brush contact area and taking round cover off and cleaning moisture and cruddy grease out. Could even be a stripped gear in it. Whenever actuator is put on you are supposed to go in reverse 3 times. This lets it find home which is fully engaged in forward. I have purposely put it in a couple notches out of forward and it still found home which is full forward. Clocking it counter clockwise by hand ensure it is at least in forward to begin with. Also is point where the detent should be engaged.

 

[Flipper]

Thanks guys. I'm pretty confident the actuator is on correctly. I actually took it off just twice just to be sure as part of my original attempt to fix.

It's going to the dealer tomorrow as I am under warranty so if I have a bad actuator or a gear issue I want a new replacement.

I'll report back on what they find and do.

 

[Dr. FeeLGooD]

Chain too tight?

 

[Flipper]

So I get a call from my dealer, they tell me it's ready to go and it was a faulty gear position sensor which I am guessing is that little sensor above where the actuator gear engages with the extension to the chaincase. This makes no sense to me given the symptoms I described earlier in the thread.

Thoughts?

I told them I want them to explain to me how this would fix my issue given the problem.

 

[Flipper]

Circling back on this.

Got my sled back and I can confirm it was not the gear position sensor. Got a grand total of two reverse engagements while the sled was cold and then it started throwing the sd-08 code again with no shift.

From what I understand the most likely cause is going to be a bad actuator given it has been working all season and I have not changed/adjusted anything in the drive line. I am going to swap the actuator out and see if addresses the issue.

Any other thoughts?

 

[Tcat100]

probably need a new top gear, and possibly reverse gear/synchro. Very common problem...the bushing in the top gear wears and the gear cocks on the shaft and the reverse syncho can't mate properly.

 

[Flipper]

Tcat100,

Thanks. That will be my next step. I only have time for 2-3 more outings this year, so if the actuator doesn't do it I'll make due without reverse and open it up once I am done for the year. That is if it doesn't fail first. I am hypersensitive to any vibrations right now...

 

[Tcat100]

Be careful though, the issue usually becomes it popping out of forward . Mine did this the week before my big trip...I'm glad I changed the top gear.

 

[Mototown]

What kind of gear oil wasin the chain case , after first maintenance?