'81 Maxim 650 Will No Longer Shift

Help!!

I've got a problem with my trans, I'm not able to shift out of neutral or 1st gear.

While riding last Friday, came to a stop at an intersection, took off and could not shift out of 1st -past neutral and into 2nd. Bike had been running and shifting fine until then. I can shift back and forth between neutral and 1st gear, and that's it. Tried to get the bike into 2nd gear and could, sort of. While holding shift lever up (hard) I could just get into 2nd, but it did not want to stay there, with a little throttle it would drop back into neutral.

Ended up riding the bike back home in 1st. Pulled the shift cover and clutch cover off expecting to see "issues", like broken parts, bits of metal and the like inside. Checked everything over and checked oil, all looked ok, no metal shavings, everything under the covers appears to be ok.

I've been told I may have a "possible" bent shifting fork or maybe something jammed in the shifting drum, but I'm not sure where to go from here.

Does anyone know if I can get access to the inside of the trans (fork, drum, etc) and look at these parts without pulling the engine and splitting the cases?

Also, I have not pulled clutch plates off yet, will do that tomorrow.

I want to get my bike back on the road! I'm really hoping this problem is not terminal...

Can anyone help??

Tom

 

Sure; but the quick fix is short term; the real fix is a case-splitter.

The shaft-driven XJs use a solid plastic block type tensioner/guide for the "primary" chain, the big chain that drives the starter/alternator jackshaft off the crank.

This primary chain guide is known to disintegrate. It's a "when" not an "if."

When that happens, chunks get wedged in the shift forks/drum and prevent you from shifting gears.

Since you've already checked out the "mousetrap" and found no broken springs or springs missing their end loops, etc., then this is likely the problem.

In the shifter "gallery" above the mechanism is a nice round HOLE that will let you see into the gearbox. You'll be able to peek at the tops of the shifter forks, etc.

Get a flashlight and a long set of hemos and go fishing for hunks of black plastic. Depending on how bad it's breaking up, there could also be smaller pieces in the sump.

If you can find and extract the hunks of plastic jamming the shift forks, the tranny will work again. Until the next piece big enough to jam the shift forks breaks off; the little ones go in the sump and start clogging up the oil pickup screen. Fun stuff.

The true fix is to split the cases and replace the bloody chain guide. Not quick nor easy.

Do a forum search on "primary chain guide" there are at least three members going through this/doing the repair right now. A couple of the threads had pics of the broken hunks of plastic like you're likely to find.

Sorry. I have a "ticking time bomb" of my own in the garage right now; I feel your pain.

Doubt it's the clutch. Put it on the centerstand and turn the rear wheel "forward" you should be able to go through the whole gearbox by "jinking" the wheel. I'm betting you won't be able to; as above.

 

bigfitz52,

Thanks for the info and the help! Finally got to checking inside the access hole, you were right, the shifting drum was locked up with 4 large pieces of broken plastic chain guide. All but 1 piece was small enough that I could pull out thru the opening, had to "melt/cut" the last piece into 2 with a heated flat blade screw driver then remove. All pieces out and bike is shifting ok. Now flushing out the tranny, checking sump for more pieces and reassembling. Getting plans together to change out the chain guide on next vacation..

Thanks again!

Tom

 

BigFitz, is there a guideline to how long the chainguide lasts? Mileage, age, or something? Is there any way to check its status before it goes?

 

BOY, I wish I could give you a solid answer on that.

They SEEM to fail pretty much after about 30K miles or so, but that's not a hard and fast rule either, we've had members on here with much lower mileage bikes and disintegrating chain guides.

Factors like the history of the bike, it's service life; state of tune (affects vibration levels) frequency of oil changes, did it do all of its sitting at once or was it on the road/off the road/on the road a bunch of times over the past 30 years, the conditions under which it sat--- all seem to affect the outcome.

Some XJs go 40K, 50K or more and the blasted thing never comes apart.

I'm not going to pretend to tell you it'll be "OK until X amount of miles" because there just isn't any evidence that I'm aware of as far as any consistency to the failure. Except that it does seem to happen a lot.

Other than staying vigilant for shards of plastic when you change the oil, there's really no way to "check" it other than pull the sump and get what peek you can at it. It's pretty well "buried" in the motor.