XJ550 Maxim won't shift gears

So out of nowhere, I get on my bike this morning to go to work and i get a block down the road and i realize my bike won't shift past 2nd gear! It even feels a little different shifting into neutral. I try to shift up and it feels like the shifting lever is stuck and just won't go any further up.

Any idea what this may be?

1981 maxim 550

 

You may have a broken spring in shifter drum.

 

What kind of miles on your XJ? If it is getting high, a broken chain guide could have sent a chunk of plastic down there, preventing you from shifting. My brain is suffering from "Friday Night Fuzzies" and i cant remember techincal terms now. There's a thingie behind a thingie that you can look in to check for chunks of black plastic in. Hopefully somebody who's enjoyed less beer will chime in and actually help here... sorry.

 

INTERNAL SHIFTER MECHANISM PARTS:

Inside your shifter case side cover are a variety of levers and linkages that translate the motion of the your shifter foot pedal into movements that operate the SHIFTER DRUM, which in turn operates the SHIFTER FORKS which then engage or disengage the various TRANSMISSION DRIVE GEARS. Worn or damaged RETURN SPRINGS can prevent the shifter from operating properly, and are the first thing to check if your bike will not go into gear, is "stuck" in a particular gear, or if you cannot "find neutral".

Of course, there may other issues which could cause the same problems, particularly the dreaded "disintegrating primary chain guide" issue, but it's always best to determine whether a simple problem exists first..........

Pictures of the inside of the shifter assembly can be seen at:

http://xjbikes.com/forums/index.php?threads/20246

and

http://xjbikes.com/forums/index.php?threads/28233


A good write-up on the typical problems and issues involved with these parts can be accessed at:

http://xjbikes.com/forums/index.php?threads/19227

http://xjbikes.com/forums/index.php?threads/48591

However, please note that the exploded diagram attachment on the 19227 page is "typical" for most XJ-series bikes, the actual mechanisms will differ slightly between different models (the diagram shown in the 3rd post is correct for the XJ650 - XJ900 models; most other models use a variation on the same theme).

NOTE: if this describes your situation:

Couldn't get her out of (whichever gear you were in when the problem occurred).

This situation can be caused wither by a broken TENSION SPRING (the small linear-acting spring) or by the TORSION SPRING (the one with one straight arm and one "hooked" arm). Both of these springs are designed to keep the pawl arm properly engaged with the shifter drum "star wheel" segment. Note there is also a long SCREW which retains this star wheel to the shifter drum; if that screw is loose, it will allow the star wheel to rock back and forth or not even engage with the drum, also resulting in the same type of issue.

On early XJ650 engines and XJ750 Seca engines, the original torsion spring used was somewhat weak, and was replaced by an upgraded spring on later model engines, which also required a slightly different spring collar (sleeve) to be fitted.


NOTE: if this describes your situation:

"Today, after a downshift, the shift pedal would not pop back up automatically."

This problem tends to be caused by a broken TORSION SPRING (the one with straight arms on both ends of the spring) which is supposed to center the selector shaft segment. The earlier 1980-81 XJ650 and XJ750 Seca models were especially susceptible to this problem, and an upgraded, thicker spring (which required a thinner spacer collar underneath) was introduced to the 1982-later models.

 

or your chain guide is breaking up

 

Hopefully it's one of Chacal's suggestions... simple problems are good ones.
PS I vow to not post from the inside of a brown bottle any more. Once the kid is asleep and the wife is on Facebook, the computer is pretty inviting...

 

Yep.... Looking back, you mentioned it, Len echoed it, and I reiterated it.

Ooooh, I spelled it correctly, too!!! Spellcheck didn't even have to correct it

 

Are there any other problems it could be? I have a similar issue with my XJ550, the bike won't shift, it feels sort of like something is getting bound up. I pulled the clutch and the shifter shaft/mechanism, all three springs on the shifter mechanism seem to be in good shape. Also with the shifter removed I can easily turn the star wheel to shift the bike into all 6 gears, so there shouldn't be any broken chain guide stuck in the gearbox. The screw holding the star wheel to the shifter drum seems to be tight as well. Any other ideas on what the issue could be?

 

Did you LOOK through the hole to SEE if there's anything in there?

 

Guys, from what I read the 550s don't suffer from teh chain guide disintegration issue - cos it ain't there..

 

The 550 does have a chain guide. It just so happens that is is a hydraulic chain adjuster with a plastic guide. The 500s have less of a problem because the chain is not slapping against the guide at low RPMs, but the plastic can break down due to age, just like any other plastic can.

 

Where would this hole be to look through? The 550 doesn't seem to have the big gaping hole in the casting that the 650's/750's do (shown in the pictures above).

I appreciate the help guys, thank you

 

Forgot for a moment that you're not on a 650/750/etc...

 

You may have to drop the exhaust and sump to check for plastic bits in the oil pump shroud/screen.

Gary H.

 

Pulled the sump, everything looks really clean. Nothing in the oil pump screen, no plastic sitting in the sump. Looking up into the gear box everything looks surprisingly clean as well. Nothing seems to look out of place...

I reassembled the shifting mechanism just to double check the issue and its still there. Although I can freely spin the star wheel and engage all 6 gears without it, when using the shifter I can only get into the bottom 4 gears and its extremely tough to shift between the those 4.

Any other ideas guys?

 

Clutch?

Gary H.