First Gear Issue

The 4th gear (splined slider) came in 3 variations.
No marking notches, 1 marking notch, 2 marking notches.
Your 4th slider should have NO marking notches, and its spline ID surface should be polished, to match the early -00 countershaft's polished spline bottoms.
4th-Slider.jpg
 
Output Shaft.jpg Polish on New Fourth Gear.jpg Teeth on New 4th Gear.jpg Feeler gauges.jpg slop obscured gears togather.jpg Slop Revealed.jpg Output Shaft.jpg Feeler gauges.jpg slop obscured gears togather.jpg Slop Revealed.jpg Hea Thanks again. Research is so much fun. We sure as hell don't do this to make money. Anyway I do have the correct Shaft and my old 4th gear has no notches cut into the gear so that's orig. The polishing on the splines looks a bit crappy/rough but the old gear slides real slick on it.
The New 4th gear was OEM packaged with the same number as you pictured. It is polished where it should be but it does have a single row of notches cut into the gear teeth tips. The New 4th gear is a bit tight on the old shaft but I didn't really lube it up yet. Not really concerned about that. BTW,
Output Shaft.jpg
Polish on New Fourth Gear.jpg
I measured the bearing ID on the old first gear vs the New 32T that I cannot us and the difference is .003. Attaching a couple of pics of gears, shaft and slop. I was unsure of whether or not to check the full image or thumbnails box. so advise if I screwed it up. My new 1 st gear ships from St Louis tomorrow so probably two days us mail.
 
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I think I should just do thumbnails since they will open up full size anyway ?? Sorry about the in your face giant pics . oops
 
Yeah, let's do thumbnails, unless really necessary.

Your new 4th slider, 256-17241-01, with 1 marking notch, is a mystery part. I have NO info on that thing except that it seems to have arrived around 1974-1975. Revised parts manuals show it to be a superceeding part, downward compatible to 1970 XS1. It was superceeded in 1977 with the great "Spline change", to p/n 256-17241-02.

Your pic has me a bit confused. Am I seeing an optical illusion, or are the ends of the dogs slanted?
1975-4th-slider.jpg

For comparison, here's my 1980 4th slider.
256-17241-02 (2 marking notches), starting in 1977
Note the straight, square dog ends.
80-XS650-Countershaft06.jpg
 
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For reference, here's the service bulletin on transmission gearbox spacing. Note that the recommended end-play for free spinning wheel gears is 0.003"-0.005", and that would include your 1st wheel gear.
71-01-15_S259-01_GearboxSpacing.jpg 71-01-15_S259-02_GearboxSpacing.jpg 71-01-15_S259-03_GearboxSpacing.jpg 71-01-15_S259-04_GearboxSpacing.jpg
 
Somewhere last year I acquired a (reportedly) low mileage '81 transmission.
Dug out the countershaft so we can compare critical dimensions.
80-XS650-Countershaft01.jpg

Because of the overlaps of shaft and gear part numbers and revisions, I'd expect these dimensions to be constant throughout the 70-83 production.
80-XS650-Countershaft02.jpg

Note that there's an unaccounted 0.004" in my measurements in the outer smooth part of the shaft. Took multiple measurements, different methods, tricky, just came out thataway.
 
I hadn't really inspected this countershaft before, but noticed that there was virtually NO endplay of the captured 1st wheel gear. Found out why.

This 1st wheel's inner bushing is displaced by 0.014"-0.015".
It shouldn't be like that.
80-XS650-Countershaft03.jpg

At the other end, you can see that the bushing is recessed.
80-XS650-Countershaft04.jpg

I don't know if this gear was run thataway, or if someone pulled a fast one on me. Just another thing to watch out for.
 
Grinding some numbers.

0.788" - Bushing bore
0.786" - Shaft OD
---------
0.002" - Running clearance

Now the axial clearance. The 1st wheel, washer and clip will be contained within the spline shoulder and far edge of the clip's groove.

0.674" - Shaft width for 1st wheel and washer
0.067" - Groove
----------
0.741" - Total

0.645" - Width of 1st wheel, with that displaced bushing
0.040" - 1mm thrust washer
0.060" - 1.5mm clip
---------
0.745" - Total

That 0.745" is a bit more than the above 0.741", no wonder it showed no axial play, and maybe that's where the missing 0.004" is.

Now, the 1st wheel is actually 0.630" thick, and that would be the true width at the bushing if it wasn't displaced. So, calculating:

0.630" - True width of 1st wheel
0.040" - 1mm thrust washer
0.060" - 1.5mm clip
---------
0.730" - Total

Subtracting that from the shaft's 0.741" would give 0.011" endplay, or a bit more.

So, it would appear that even MY countershaft's 1st gear axial clearance would be too much, and would need tweaking, to get it down to 0.003"-0.005". The actual clearance would be done using feeler gauge, as you've been doing.

So, in summary, this is a cross check to see if your shaft, old gear, and new gear, match the dimensions I've found.

Secondly, I'm glad you brought this up. What with the sporatic history of 1st gear hiccups, and finding neutral, this could be something to add to the list...
 
WOW 2M. awesome specs. And I know that was some work.They USPS mailed my new first gear this morning about 10 so I am thinking that it will be here when I get home from work Wednesday. and Yeah I knew there was no way that .054 was anywhere near acceptable.
Your spec "0.003"-0.005" for a free spinning wheel/gear sounds right BUT I cant wait to get the New First Gear because what I calculated said that even if I added the additional Thrust washer beside the existing one to move the gear to the right, I would still have .013 clearance.
btw I miked my new washer at .037. Thanks also for those spec sheets. I will go over them closely and when My gear arrives I will post back a coherent orderly analysis of what I see. Thanks a million.
btw. I have not yet added that New shift fork. I verified that the Cam follower 2 pieces were fine and installed and then I loaded first gear the fork up to the Left and measured between each tip and the smooth polished engine case to the left of it there was exactly .001 difference. Don't think that is any part of this issue. LTR
 
OK so here are the New Comparison specs that I have gathered.
My Drive axle has a bit of taper. It measures .7870 at one end and .7855 at the other end. That's .0025 taper. not huge

Width of New First Gear .6300
Width of Old First gear .6255 That's a difference of .0045

Bearing difference New vs Old New .7860 Old .7880 a difference of .0045. That makes it hard to measure the clearance between the gear and the distance washer accurately. That's why I got the .0052 measurement earlier.

Distance Washers. Or shims. Old one was .0380 and I had 3 new ones. A .0385 and another .0385 and One that was .0400 I am using the .0400

Shaft Distance. I installed the Snap-ring ".058" into the groove
I measured from the machined boss on the shaft to the snap ring/installed and it was .6805
I calculate the gear Width..6300 plus the shim .0400 and get .6700.
I subtract the available area on the shaft .6805 from the combined gear and Shim .6700 and i get .0010
That should give 10.5/1000 side play on first gear on the shaft. Which sounds fine I think. This a New First Gear and a New Fourth Gear that are going to be used.
May not comply with the chart. I still need to reference that.
Installed Measurement. Once installed the accurate clearance with a gentle drag on the feeler gauges was .013. 13/1000. I think that that is usable. I really don't want to back up and replace the shaft for 2.5/1000 taper

I will go and blow up those charts now and see what comparison specs are shown.

Noteworthy. I am uploading only one pic tonight and it is of the New First gear. I hope that you can see it . It appears that where the 4th gear dogs touch the First gear, the First gear surfaces have a bit of a bevel built in. "not just at the corners bit on the face of the engagement point. pic not really revealing more than the edge taper bur it kind og looks like the whole surface is crowned. too hard to measure that tonight.
 

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Good crosscheck on those dimensions.
I hope these new gears solve your 1st gear problems.

Yes, I can see the "crowning" on those surfaces. All the other gears I've examined have flat surfaces, with a gentle rounding of the corners. We've mentioned here before about avoiding whimpy shifting, especially entry into 1st. Avoiding that, I don't think the crowning will be an issue.

Something else you may want to do is to smooth/polish the thrust faces of the 4th dogs and 1st slots. Should help with finding neutral while stopped...
New First gear01.jpg
 
Jeeze, AMEN to that.... That New 4th gear was tight as hell. With a little dressing off and Oil it moves pretty good now but I am going to massage it a bit more. I feel really good about getting the slop from .052 down to .013 and with New Gears too I feel even better. I will smooth and polish everything. Especially where 4th gear mates to the shaft. I will let you guys know the result. Thanks for all of the support.

OOOOH and hea.. if anyone cares or needs some I have ordered 8mm White Silicone Cord. I have not installed it yet but I am going to us it to replace the Cylinder Head Vibration Dampers. Totally heat resistant up to a bazillion degrees and should be a nice touch for completion. I am thinking that that was 1970 only ??? or was it also 71 ??. I feel like an idiot loosing mine because i knew that thy would be hard to find.

I will see how much I have left once I determine the correct length for an interference fit and cut mine and a spare set. And after that I would be happy to mail someone a set foe nothing or provide the manufacturers URL. I bought two feet. Site hard to navigate and at first I ordered 80 feet or so of the wrong diameter HaHaHaHa. The guy was cool and sent me the two feet for free.
 
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It's unfortunate, although great, that you're massaging the fit of these parts. I'm following this like a wolf on the trail. Not sure if you've seen this, adventures in finding neutral:

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

From that, I'm pretty convinced that the elusive neutral issue comes mostly from the complicated articulations of pulling that 4th slider outta the 1st's slots. Now, we want that thing to stay in there during 1st gear launches, but would be nice to be able to easily pull it outta there in spite of the minor clutch drag.

What I've sensed is that the shift actuation components easily enter "bind" when the effort to retract that 4th slider is increased. Hence my suggestion to polish the thrust side of the dogs and slots.

And, now that I think of it, especially with your reporting on the tightness of your new 4th slider, I'd like to advocate polishing the thrust surfaces (sides) of the shaft's splines and 4th slider's splines.

I've figured that there would be about 2 ft-lbs of torque being applied to the splines, slider, dogs, and slots, during the 1st-to-neutral shift. If you held the shaft, with the 4th slider fitted on the splines, and applied that 2 ft-lbs torque in the thrust direction, feel for the amount of drag while sliding it back-and-forth on the shaft. The goal would be to reduce, minimize, that sliding friction.

The only fin damper thread I know of:

http://www.xs650.com/threads/fin-vibration-absorbers-for-a-xs-1.47937/
 
Hi Mr 2M / "wolf on the Trail", Been ill for a day or 4 but got back at it today and here is the current state.

1. Thanks for your interest and all of your input. Of course as you know, " It's not over till the Fat Lady sings"

2. Today, I used a dremmel bit and eased the entry surfaces to the Fourth gear and followed that with a 1/4 in polishing barrel on the dremmel and Red Rouge Polishing Compound. Probably should use something more agressive but After I cleaned it and oiled it and installed It moved quite nicely. DONE

4.
Regarding other things I found the center-most gear " 3rd gear" to be at .005 so no issue there. Done

3.
I found Two shims for First Gear that if used together instead of the original will reduce the .015 to .007. They were the 137-17427-00-06 as shown on the chart you provided. I believe that they are the stainless shims like the ones at the bearing end of the shaft as opposed to the 90201-20266-00 which appear to be much harder. The new shim will be a tad bigger at the OD but no concern because where they are used the OD is of no concern. I could not find The correct shim in anything other than my existing thickness which is as yours .0395 or .040.
Not Sure about This. I'm thinking the Side-load is only while engaging so the material difference may not matter ??

5. Then I found 5th Gear to have .020 end clearance so I found what looks appropriate to correct that almost. There as a shim on either side of that gear and they are both .038. I found a pair that were .046 so that will correct 5th gear from .026 end-play to .010 end-play. Much better but still ways off. Better
 
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Scooterbrain, hope you get to feeling better.
We'll tell the fat lady you're contagious, keep her away for awhile.
Otherwise, sounds like you're progressing well.

Normally I'd prefer to use hardened thrust washers, but, like you say, the side load on that 1st is only intermittant. There IS another side load on it, during the kickstart gear's sideward engagement, but that's in the inward direction. It's enuff to induce a tipping/tilting force on the 1st wheel gear, perhaps the cause of the taper you reported on the shaft. If it's allowed to tilt enuff it *could* apply pressure on the shim. But, again, only momentarily, and that area is awash in oil anyway.

Good that you're checking the side clearance of the 5th. The freewheeling 5th is straddled by 2 shim washers. My manual shows 2 thicknesses available for those straddling shims, 1.0mm and 1.2mm. Those can be used to adjust gear position, engagement depth and dog clearance.

You may want to review member Glennpm's thread on 5th gear. He gets into the shimming around post #75.

http://www.xs650.com/threads/overdrive-5th-gear-dropping-slipping-out-to-neutral.41539/
 
Three pics added.
So, My shims are not here yet, maybe tomorrow. See compared Old Fourth gear slider against the new and see how the new gear does not have the splines cut down where the gear back-seats against the shaft when first gear is Dis-Engaged.
It binds horribly of course. I thought that the location of the fork might prevent it from moving that far but that is not the case. Note how the splines in the shaft grow taller at the back-seated position. The old fourth of course does not bind because it is relieved to accommodate that.
Its not hard to fix and I will of course with the dremmel but man, wow, Maybe my part is from a later model and was just slipped into a nice wrapper with the correct number OR maybe it was a gear that never got cut down properly from the manufacturer.

That's all for now.....
 

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...See compared Old Fourth gear slider against the new and see how the new gear does not have the splines cut down where the gear back-seats against the shaft when first gear is Dis-Engaged...

Well, now I'm confused.
A close-up of your "side-by-side" pic:
Side-by-side02.jpg


The gear in the backround has the rebated splines, has the 1-notch markers atop the gear teeth, and would be the newer -01 revison. That gear should work on your -00 shaft. I understood that this was your new gear.

I don't know what the gear in the foreground is. It won't work because it doesn't have the rebated splines. Is THIS actually your newly received gear, and the backround gear your original?

The shaft in your 3rd pic looks to be the correct -00 early version, used from '70 to mid '77. They have the reduced diameter splines under the 4th slider, up to just short of the circlip.
 
Ok I have Mis-described something but here is the deal. The gear in the "Foreground" that you marked ??? is the one with the taper on the splines is what was installed on the bike when I bought it. It slides smoothly even when jammed up against the stop it does not bind.

The Gear in the background that you marked -01 is the Gear that I bought New in the "Open" packaging that I posted the picture of. That new gear is tight getting started on to the shaft but once it is on the shaft it slides well over 85% of the shaft but it does get tight and flat ass stuck if it is pushed further towards the area where the splines of the shaft increase in thickness.

I wanted to use That new gear to mate with the new first gear that I had bought because it of course has New dogs.
It seems to me that all I should have to do is finish easing the material away from the area where it is binding on the taller area of the splines near the clip so that it can move easily across the entire length of the shaft with ZERO resistance. It seems do-able to me with a little dremmel work.

Most of my issue I believe was the .052 side clearance on the First gear and its additional 1.5/1000 bearing slop so I could maybe use the Old 4th gear slider but I would rather use the New one. By the Way......My new shims arrived today so I am ready to get back at it
 
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