First gear fix part 2

[Kevin W]

Hi all,
I'm at the end of part 2 getting ready to take my dremel drill to the gears. I wonder if someone can tell me if this shift fork is in need of replacing. This is the biggest motorcycle repair I've ever tried so be easy on me

My first attempt at pictures too. Hope this works.
Thanks for the help.
KW

[79XS11F]

I don't think that scuffing is suppose to be that far up the fork. I would replace it being that the trany is apart. Would be a shame to have to 2nd guess your repair if it does not shift smoothly.
Rob

[Kevin W]

I'm starting to worry that I might have "over dremeled" my gears. I base this on addition reading in the repairs section when I was looking for how to move the washer to the other side of 2nd gear for more mating surface with 5th gear. Here's a picture of how I grinded down the dogs on 4th with my file.

I'm not sure what the finished product should look like. Sharp corners?
KW

[Kevin W]

http://i222.photobucket.com/albums/d...440/4thdog.jpg
Didn't remember how I got the first picture. May this?

[JWSanders]

I fixed the second picture...it was perfect other than you left off a [ from the first IMG tag.

[TopCatGr58]

Hey Kevin,

These machines and their gears are quite sturdy! I had one that was so worn that I had to use a cut off disc to cut it right where that gear notch you see in your picture runs thru the dog!

The angle might be a little bit more that what you need, only need a couple of degrees. The bigger problem is doing the same angle to the 1st gear slots! If you have access to a die grinder, it will probably work faster and easier than the dremmel!

Also, if you'll contact TRBIG, he has some of the 1mm thick washers to replace the 2mm one you have that fits inbetween 4th and 1st gear.

Once you have it all together, don't be surprised if it takes a bit more shifting effort to shift OUT of first gear due to the stronger engagement! Looking good!
T.C.

PS, yeah, that fork looks like the PO kept pressure on it to keep the bike in 1st gear, it's only aluminum, gets worn fairly easily against hardened steel gears!

[79XS11F]

Is it true that Yamaha replacement gears if NEW are now undercut like you guys are doing ?
Rob

[TopCatGr58]

Come on Rob,

Any "GURU" knows that! But, yes the NEW ones are already undercut to help prevent this malady!
T.C.

[79XS11F]

I just wanted to make sure it wasn't an urban myth ...
Rob

[somesuch]

Re: First gear fix part 2

Originally posted by Kevin W
Hi all,
I wonder if someone can tell me if this shift fork is in need of replacing.
KW

This shift fork is gone and it definitely needs to be replaced.
--Nick

[NemisusDM]

Hey Kevin,
I back cut both sides of the gears only cause I like hard down shifting but, it's not necessary. It just sounds really cool, like an Imperial Speeder Bike flying by...

[Kevin W]

Where to put the washers?

Hi everybody,
I'm almost ready to start the reassembling of my transmission. I have a few more questions. With the transmission in front of you on the bench, middle drive gear on the left, 5th gear on the right, which way does 5th gear spin? I thought I was grinding the correct side of the second gear slots but now I'm not sure.
I read in another post about changing the plate washer spacing to get more surface contact on the dogs and slots. Is it OK for second wheel gear to "ride" against the circlip and put the plate washer against the drive axle? For first gear I was going to put a smaller washer from TrBig between the 4th wheel gear circlip and the 1st wheel gear collar and then another small plate washer on the circlip side of the middle drive gear. I hope that makes sense. Thanks in advance for the help.
KW

[trbig]

Kevin,

Your washer placing will be correct. If you look at the washer from 2nd gear, you'll see that there's really no wear on it. There has been a lot of people that swap that washer to the other side of 2nd with no ill effects.

I don't know the actual spinning direction, but with the way you have the gears situated, the pressure would be as if the top of 5th gear and dogs were spinning towards you and the top of 2nd was spinning away from you. If looking at it from the 5th gear side, the left side of the dogs are what's used on acceleration.


Tod

[TopCatGr58]

Hey Kevin,

Okay, here's a copy of the diagrams in the tech tips which shows which edge to grind as if you were looking at the 2nd gear wheel thru the hole where 5th gear slides out!



And below is a photo by Ken Talbot showing the same location of the worn slot, the left side of the slot on the top, viewed from the same orientation.


Well, if you were going to get those thin washers from Tod, then why not put one where you would have left just the bare C-clip?
But like Tod said, several have just used the C-clip without any problems! YMMV! Hope this helps!
T.C.

[trbig]

If he puts one of the thin washers where he takes the thicker one out to move:

1. He's defeating the purpose of moving the washer to begin with.. (to get it closer to the dogs).

2. He would be then trying to squeeze 3mm worth of washers in a spot where 2mm is a tight fit.

And.... I only sent him two washers which he needs for 1st gear.

Tod