Jumps out of First gear

Hello all!

I just got a free Seca 750 and I'm starting to get it into riding shape and one problem that I just ran into is that it jumps out of first gear.
So far, I have changed the plugs and oil and that is it. The rest of the gears work fine. It will stay in first until I gas it a bit and then it jumps to neutral?

Any ideas would be appreciated!

Thanks!

 

The tranny's on these bikes are one of the weak spots. While it is more common to lose 2nd. gear this is still a characteristic early 80's Yamaha transmission problem. Even the V-Max and Ventures has this. Only way to fix is to remove engine and diassemble. Then check free end play on the gear shaft and maybe under cut the gear dogs.
Some others here may have some better info for you. So wait for their input. Congratulations on the free bike. I would still say it is well worth owning. I loved my Seca and still want another one to go with my current Maxim. I know some who have lost 2nd gear only to shift past it and ride their bikes for years like that. They just love them too much to let that stop the fun.

 

Yeah, I have the same problem with my 82 maxim. The previous owner said he just kept his foot on it until he was ready to shift, but I just use first to get moving then shift into second. Every now and then it will jump out before I'm ready , usually in the middle of an intersection, and make it look like I don't know how to shift.

 

So it sounds like I should let the local shop take a look at it to see what it would take to fix it. Since I'll work on the simpler things on it but I'm guessing that I would get over my head quick with this.
It's just weird because when I can get it to stay in first gear it works great. It's fine when I gas it to get moving but as soon as I back off the throttle a little it drops to neutral.

 

Well, letting the local shop do it is an option but you run the risk of getting the lowest paid mech doing the job. I would only let someone else touch my machine if I were confident in their abilities. Do you know the folks at the shop? Do they run a smart outfit? How clean is the maintenance bay? You should ask for a tour of the facilities to gauge how serious they are about what they do.
I'm all for pulling and doing the job yourself but this is dependent upon your skill level and willingness to dig in. Since you seem a little hesitent, it is probably wisest to leave it to the shop.
If you can change your oil and know how to split a bearing off a shaft, I expect you would have all the skill going into it that you would need. Knowledge is only a book away and we (collectively) are at your service to help you through the rough parts.

 

With this bike having a somewhat unusual -- "Jumping-out of First Gear ... rather than Second Gear ... I think it would be worth the time to take-off the Shift Cover and see how the Claws and the Stop Arm on the Gear Change Mechanism are looking.

I would at least give FactoryPro a call and tell them what you got.
800.869-0497

Ask if this Shift-Kit will do anything about you losing first:
http://www.factorypro.com/

 

Well, I do a lot better with computers than I do with mechanics. I do have a friend that is a car mechanic that I can get to take a look at it since I would prefer to do the work myself.

 

Here is a link to a article that explains how to fix it. I have done this on my XJ1100 and it works, the trans shifts better than new. Your trans is the same design this one and the same techniques will apply.

http://www.xs11.com/forum/showthread.ph ... eadid=5090

The XS1100 website has many helpfull articles

Mark
XJ1100
XJ750
XS1100

 

That's an amazing article. I had no idea you could get to the tranny with the engine in the motor. I would never have guessed it was possible. Is that the case with all XJs?

Greg

 

Bloomin' brilliant! I'm gonna petition this link be added to our sticky file!

 

Ok...I'm in deep doo-doo now! I talked to my buddy and he's all gung-ho on tearing it down and playing! Guess I'm going to learn about this bike faster than I had planned! :lol:

 

If you go after the gears like this fine article shows:

How long does this fix hold-up before actually needing to overhaul the trans and install new gears? And, why not just replace the gears if the damage is really bad; anyway???

I wish the author had included some close-up's of the Shifting Forks and how they move the Gears when the transmission is shifted.

Additionally, if you are diving-in to fix your bike from jumping out of gear ... and you're bike is in the "High mileage" group (50K+) ... check the clearances on the business-end of the oil pump.

 

I tend to agree with you on that...I was wondering what it would cost me for new gears since it would be out anyway.
My bike has about 37k on it.

 

I would venture that your gears are probably fine. In my (meager) experience, these kinds of problems are almost always shift fork related.

Greg

 

Now I have something to study for the next few days. I had no idea the tranny parts could be removed without splitting the cases. Great info and thanks for it!

 

I'm with Greg ...

If you have 1st Gear popping-out ... and, you can "Hold-it-in-gear" by keeping pressure on the change lever ...

Classic bent fork.

The fork gets bent because the clutch isn't adjusted and the PO took his frustrations out on the shift lever.

You have a fork that got bet and can't move the gear over far enough for it to fully engage and stay in place.
Pushing it in place by holding-down the lever worked for awhile ... but, eventually, the inside of the fork is worn-away by metal to metal contact.

The fork being the softer of the two metals wears away to such extent that the "Throw" to push the gear along the change shaft is so far off -- due to the bend and the subsequent abrasion ...

The gear only moves as far as the damaged fork can move it. Not nearly enough to fully engage ...

pretty soon ...

First gear disappears all together and you have to start holding-it up in second.

 

So since I haven't bought a manual yet...how hard is that to get to? I would assume it's easier than replacing the gears?

 

Oh, yea ...

Getting a manual is a cinch.
Flipping the pages is easy and you don't need any tools.

Doing the stuff outlined on the pages ...
Cancel that Tee-time.
It's time to play "Wrenches"

It can be ugly for a few hours. Then, the mission is accomplished and you're back getting sunburned on your way to no place specific ... just riding and looking at all the sights.

If Peru wasn't two-days distant. I'd be right over to help-out on this one; just to hang-out and watch and see how it goes.

 

If the method outlined in that page works, then it might not be too bad. Pulling the motor and splitting the cases is a job I wouldn't wish on many.

I have a Seca turbo motor sitting in a thousand pieces on my workbench because I decided to try this. Someday, I hope to have it back together!

Greg

 

SUNBURNED? I don't want skin cancer, so I'm glad to have my SPF infinity helmet and leather jacket

 

Manual is on its way! Once I get that then I'll have to get my buddy over here to help me with it.

 

to bring up an old thread : How did you go Chitty?

 

and is the xs11.com website closed down???

 

I think I found the xs11.com website. It's now here:
http://www.elbarfo.com/component/option ... /Itemid,1/

 

Again, I hate to drudge up an old topic, but I also know from previous experience in other forums for the dislike toward starting new posts with old topics.

I just got my '82 XJ750 on the road yesterday and noticed it jumps out of 2nd gear all the time, and 1st when I jump on the throttle. 2nd gear will not stay in, regardless of what I try. To shift, I have to easily apply the throttle in 1st, then jump straight to 3rd.

I have read a few articles before I finally joined up on this site, and have come to the realization that I have a huge job ahead of me. However, my neighbour is under the belief that repairs can be made through the side covers on the engine.

I have talked with a motorcycle mechanic friend, and he is under the similar impressions to the information on this site: the engine has to be removed and split apart.

Given the price I purchased this bike for, plus the slight amount of money I have into this bike, I have a perfectly fine rolling chassis, with a bummed tranny. I do not want to pay someone to make the repairs, because this bike just is not worth sinking that kind of coin into.

Any suggestions to where I can locate an engine to swap out? Is it possible to make the repairs, hopefully to a bent shifter fork, through the side cover?

When I changed the oil a week or so ago, I saw no metal filings in the drained oil, nor did I notice any metal filings in the oil filter. Any suggestions? Fix or sell?

 

There's no easy fix for a transmission that's jumping out of gear.
You need to do more than replace a bent Shifting Fork.

You also have to re-face the surfaces of the Dogs on the sides of the gears that are worn-down and giving way to the torque and rejecting the gear change.

I think the easiest way to address the issue is to find yourself a substitute engine.
Look for an engine or the ever-present "Parts Bike" and buy an engine (or cheap whole bike) that passes the basic tests for substitute engine-worthiness.

AFTER you get the Bike running with the substitute engine ... you can take your own sweet time rebuilding the Original engine's transmission; replacing the worn-out parts with new ones and making yourself an engine to power you into the years ahead.

 

To do any work on a bent shift fork, how hard would it be to make these repairs by removing the side covers on the engine?

 

Quite impossible as access to the forks can only be obtained by splitting the case. Sorry to be the bearer of bad news.