First Gear Issue

[Scooterbrain]

1970 650
Guys I have been reading here for weeks and still not sure what the issue is here. I pulled the engine out last week and while the First gear Fork looked bent, even looked like a slight twist maybe.When I straightened it it was too tight so I restored it to where it was and it shifted fine on the bench.

I did find that I has omitted the second shim that goes behind the Clutch Boss. Now it is "Shim, Flat Bearing Shim. I also found that my manual only showed One ball used with the Clutch rod instillation so I corrected that to a ball at either end of the Clutch Rod.
It shifted like a dream in the bench. Went all through the gears up and down 4 times and said OK. When I hold the Clutch assy in both hands I can lust barely feel it move a tad when I try to rock it back and forth so that felt correct.

Once it was back in the bike "Not Running" it shifted all gears just fine I could shift through all gears through the entire range although I did have to move the rear wheel a time or two to get an engagement and snap it went right in.

Then On the Bike lift I cranked it up and ran it and I had no issue at all getting it to shift into any gear but it did seem like I had to brake to stop the rear wheel from turning while I was in a gear and had the clutch pulled in. I figured cold oil and clutch so I figured it would be OK. NOT !!

I cranked it up and selected first and it went right in. I drove 10 Feet and it jumped out of First. I try to again select First and you can hear the Three Dogs trying to enter the Three corresponding holes and it just goes clunk clunk and wont go in.
I cannot see any wear on these gears at all But I also do not see the bevel or taper that guys are talking about restoring to these gears. The Shift Forks have a Full Pad look and seem to have no wear. This bike had this issue when I bought it and I had assumed that it might be the broken end on the shift arm that engages the end of the drum and that is now New and it is centered per the diagrams with equal distance left and right and the lock not it tight. Only thing I wasn't happy about on reassembly was the slop in the First gear on the shaft and I resisted my thought that I should add another shim there behind the snap ring.
All I know to do now is go for a new First And Fourth gear and a New Fork . ???? I am glad you guys are here and I did read till my eyes were bleeding before posting this.

 

[Scooterbrain]

When I said "I figured cold oil and clutch" I meant Cold oil and New Clutch.

 

[TwoManyXS1Bs]

Hey, Scooterbrain.

Before we get started, do you have the 'good' parts manual?

https://thexscafedotcom.files.wordpress.com/2014/07/xs1-xs1b-f-xs2-parts-lists.pdf

 

[Scooterbrain]

Well, i do now ! Thank You very much. Thank you very much . I have been relying on partzilla so far for pat numbers

 

[Scooterbrain]

btw. They weren't that expensive so for the trip back in I bought a new forth and First gear last night while they were still available. I was unable to find a New fork though. I am beginning to wonder about the shift drum. It did have it fully disassembled in the first build and it did have 1 stiff cam follower that I had addressed to my satisfaction at the time

 

[XSLeo]

These clutches have enough drag when the lever is pulled to keep the wheel turning when up on the center stand. Thus having to use the brake to stop the wheel. When on the ground this won't happen, the drag won't pull the bike, if it does you need the adjust the clutch.
On the taper on the dogs, It is very slight and just looking you may not be able to see it. A small square may help.
Leo

 

[Scooterbrain]

Thanks Leo. I suppose that I will have eliminated that as a possibility when My 2 new gears do get here. I will be able to compare them at least. Do you think that there would be any harm in adding my spare 20-25-1-00 Gear hold washer beside the existing one to get some of the slop out of First Gear ? It sure looked like there was room for another one the last time that I was in there ! Maybe it needs a little slop....I don't know. I sure wish I has a Workshop manual that had a spec on that.

 

[TwoManyXS1Bs]

... Do you think that there would be any harm in adding my spare 20-25-1-00 Gear hold washer beside the existing one to get some of the slop out of First Gear ? It sure looked like there was room for another one the last time that I was in there ! Maybe it needs a little slop....I don't know...

Wait until your new gears arrive. Sounds like your existing 1st wheel gear may have some wrong dimensions, bore diameter, slop, width.

The 70-71 trans use a 14/31 tooth combination for 1st gear. 72-on, 1st gear is a 13/32 tooth combo. Double check your gear tooth counts.

Best I could figure, gears 2nd thru 5th have the undercutting. 1st gear dogs are straight.

You may want a second look at shiftdrum stopper plate. There should be NO in/out lateral play of the shiftdrum. Some info on that in here:

http://www.xs650.com/threads/finding-neutral-while-stopped-and-in-gear.47568/

 

[Bob Kelly III]

......OK......1st and foremost..... Never straighten a shifting fork ! REPLACE IT !!!!! they are within thousandths of an inch in tolerances they have to be for the bike to shift correctly..... REPLACE that bad shifting fork ...or ALL of them if they look burnt replace them ! Period ! simply because your having shifting problems..... if the gears look good leave them alone , the shifting forks are the issue !
the gears can ware on the shaft and allow wobble of the gear when sliding if they do have side to side wobble, replace them !
the transmission is a precision instrument ... it has to be in specks ! to work right !
.... that's my opinion obviously..... fwiw !
Bob........

 

[Scooterbrain]

......OK......1st and foremost..... Never straighten a shifting fork ! REPLACE IT !!!!! they are within thousandths of an inch in tolerances they have to be for the bike to shift correctly..... REPLACE that bad shifting fork ...or ALL of them if they look burnt replace them ! Period ! simply because your having shifting problems..... if the gears look good leave them alone , the shifting forks are the issue !
the gears can ware on the shaft and allow wobble of the gear when sliding if they do have side to side wobble, replace them !
the transmission is a precision instrument ... it has to be in specks ! to work right !
.... that's my opinion obviously..... fwiw !
Bob........

Understood Bob ! any idea where I might find a NEW First gear fork ? I did a thorough search for a new fork P/N 256-18513-00-00 and I found nothing. Closest I came was a set of forks on ebay that looked like hell for $19.00

 

[Scooterbrain]

Wait until your new gears arrive. Sounds like your existing 1st wheel gear may have some wrong dimensions, bore diameter, slop, width.

The 70-71 trans use a 14/31 tooth combination for 1st gear. 72-on, 1st gear is a 13/32 tooth combo. Double check your gear tooth counts.

Best I could figure, gears 2nd thru 5th have the undercutting. 1st gear dogs are straight.

You may want a second look at shiftdrum stopper plate. There should be NO in/out lateral play of the shiftdrum. Some info on that in here:

http://www.xs650.com/threads/finding-neutral-while-stopped-and-in-gear.47568/

Thanks 2M I will gave a really close look at the new vs old when they get here. I am ready to open it back up but I sure hope a New Fork becomes available somewhere.

 

[Bob Kelly III]

Sorry ...Not a clue.... Did you try Mikes XS ? if they don't have'em try gggGary PM him and see if he's got what your looking for !
....
Bob........

 

[Scooterbrain]

Yeah I tried Mikes. All they have is bearings, seals and 5th gear. at least on the site. I will email them just for the heck of it. I would love to have a new one but If I cant I might do as yu said and hit Gary up.

 

[Scooterbrain]

Might be a littler easier than I thought to find a good used one. I see now that the 1970 number for the fork is the same as the 75, 76 and even the 1981 so that,s a relief. there are plenty used ones out there that look pretty good in sets.

 

[Bob Kelly III]

Seriously, gggGary is back and he has the biggest parts inventory that I know of ! he will not steer you wrong ! he's a good guy !
if the parts are bad he won't sell them to you for love nor money ! so you can count on him ! I'ed rather deal with him than Mikes anyday !
.... LOL
The Baron of Baraboo has the shed of Ill repute open now so ask him ! what's it going to hurt ?
.....
Bob......

 

[Bob Kelly III]

the reason I am so adamant about replacing the shifting forks is on a Honda 90 about 45 years ago I opened the case because it was getting really hard to get into 4th.... sense I used the bike all the time and needed it for transportation I tore it apart and found the forks on 2 of the shifting forks were burnt badly and one was even bent like you described... so I did what any Ranch kid in the situation would do ...I took a hammer to it and bent it back where it looked right.... put it all back together that night so I could use it in the morning and on the way to high school it started popping out of gear it didn't matter what gear...any gear so I asked a few of my school buddies and found a friend that had a basket case 90 just like mine for $20 bucks I bought it and replaced the entire shifting fork drum and forks slapped it back together and it worked fine for years ! ..... come to find out when I took it apart I compared the fork I straightened with the one I was replacing it with and the entire Fork was bent down a good 1/8" to 1/4" .... I was into the bottom end of that poor engine many times and finally got it right.
but the top end kept seizing up on me and I had no idea why.... My Dad said it's probably running too lean do a color test ...I said what's that ? .... and that started my Motorcycle mechanicing career LOL Dad was no dummy when it came to engines but the motorcycle scared him
he knew nothing about it and didn't wann'a know either ! .... damm Jap things anyway ! LOL but his Hot Rod days were sure exciting !
flat head v-8 with 3-2's and straight pipes and tuned headers.... he would go through a set of rear tires in a week ! LOL
..... I remember asking him how a 2 stroke works... I knew how a 4 stroke worked but a 2 stroke was new to me so we sat all evening talking about engines..... tuning and timing changes, things you can do and things you can't ! .....
I guess that is why I'm so mechanically inclined hehehehe I finally talked him into a Honda 1100cc Shadow what a heavy beast
but he loved it..... finally when it fell over and he discovered he couldn't pick it up he sold it to me ! HAHAHAHA!
I told him if I can pick it up off the ground I'll buy it from ya ! he said Ok and smirked .... I laid it over on its side and picked it up without too much effort at the time.... but it was very very heavy.... now I couldn't do it I'm sure !
but I had that bike for years made it into a cruiser ! had my first bad wreck on it and fixed it back up ..... then the ranch fire Melted it !!!!!
...... lol such is life I guess !
Later !
Bob........

 

[Scooterbrain]

Thanks Bob. I will let you guys know how it works out it. I am sure that the New parts and attention to detail will provide the answer.

 

[TwoManyXS1Bs]

... I see now that the 1970 number for the fork is the same as the 75, 76 and even the 1981 so that,s a relief. there are plenty used ones out there that look pretty good in sets.

Yes, the 1st/4th shiftfork is the same for all years.
All that changed was the special groove pin (2-part roller to 1-part solid)...

 

[Scooterbrain]

Just an update here. My gearing is correct at 14-T 31-T for first gear. My Fourth gear arrived New and ok but the First gear I bought on description which was wrong and they sent the 32 T gear. I got lucky a few minutes ago though and Bought a brand new new one from archway International MC salvage for $15. yeehaah ! so I will have to wait a few more days now.

Anyway I would still like to know what you think about the slop. If I install the new gear and still have the 52/1000 slop that I have now, I am gonna be real inclined to use one of the extra 37/000 washer plates 90201-20266-00 between first gear and the lock ring. That would leave 15/1000 which seems nice. It would place First a tad closer to the Fourth gear dogs but not too close.
Glad I got a new Fourth too because the dogs were a bit rounded on the drive side.

 

[TwoManyXS1Bs]

That 0.052" slop bothers me. Spent the day researching that 1st gear and found some remarkedly similar gears from different engines. Wondering if a wrong gear was slid in there at some time ago.

I'd still wait for your new 31T gear, see how it fits.

In the meantime, you could check your countershaft (output shaft, drive axle).
There were 3 versions.

256-17421-00 Used on 1970-1977.
The spline bottoms are polished.


256-17421-01 Used on 1977-1979(?).
256-17421-02 Used on 1980(?)-1983. (Shown below)
The spline tops are polished.


I have no info on the -01 to -02 differences.
I think they're interchangable.

You should have the first version.
If not, we'll need to review the entire trans.

256-17211-00 1st gear wheel, 31T, 1970-1971
306-17211-00 1st gear wheel, 32T, 1972-1983

The fact that the 306 gear remained the same during the 1977 shaft change implies that the shaft end where that gear rides remained dimensionally unchanged. Unless there was a machining error, cutting the retension groove and/or the spline shoulder in the wrong place.

So, if your new/correct gear shows the same lateral slop, we may want to go in depth on your countershaft...