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Tranny xr600r doesn't rotate freely

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After this: http://www.thumpertalk.com/forum/showthread.php?t=852784&highlight=

I finally collected all the parts, had my crank conrod replaced and cilinder nicasiled.

Just finished assembling and dissassembling my bottom end 3 times... :banana:

The problem is the clutch- and front sprocket-shaft rotate are turning very tight.

Engine does shift alright....

I can just barely rotate them by bare hands... :lol: It's just like the gears (the teeth) are being pressed into each other very tight or something. When the cases are splitted, they turn fine...

When I temporarily install the clutchhub to have something to hold on to, you can turn it over, but you feel the teeth running..

The shafts do have some axial play.. I gently tapped on the shaft-ends and they move a bit... so they are not locking bearings or something..

Is this perhaps normal for these engines? What could it be? Bend tranny shafts?

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I already did that.... I'm sure the shaft is build up just like in the workshop manual diagrams...

I thinking the mainshaft and/or countershaft is bend.. When you put a bend axle in a bearing, the bearing spins very tight/bad.... that could be it..:banana:

The engine did chew up a big piece of piston... :lol:

It sucks that I now need another gasket for the cases when taking it apart again....

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I have all the dimensions of the Gearbox washers in mm if you have confusion

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It's quite the problem you have.

It's like the two shafts are too close together - if the gears aren't meshing. But, in my experience, you need to look everywhere. Check your shafts for any bends - inspection tools are needed. If everyting is assembled per schematic, it's either that or the bearings.

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Ok, I really dont mean to hijack this thread, but I'm also doing a bottom end rebuild and I just can get my tranny to turn right when I have the cases split. Im kind of getting a little po'ed at this, and could really use a little help, so if someone could PM me with some help

thanks

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I've thought about it for a while now, and I think it's the shafts being bent..

Mainly because large parts of pistonskirt went through them.

When I engage the gears in neutral, I have to turn over the countershaft (one with the front sprocket) with a gripper. If that shaft is bent, it will make the end bearings run very tight/ lock up..

I can easily test this by removing all guts from the cases, and just installing one of the shafts, and bolt the cases together. See how it spins.. Too bad I will need a new gasket now..

I'll try this tonight... Damn those shafts are very expensive... :banana: (about 300 dollar per shaft here in the netherlands...)

Edited by Ilja

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Ok, I really dont mean to hijack this thread, but I'm also doing a bottom end rebuild and I just can get my tranny to turn right when I have the cases split. Im kind of getting a little po'ed at this, and could really use a little help, so if someone could PM me with some help

thanks

I won't p/m you but I can tell you that the Gearbox rarely turns freely/shifts easily until the two cases are together.. Even then you sometimes have to rotate the Countershaft sprocket/shaft at the same time as trying to shift through the box.Their's just too much movement and flex in the parts when they are just flopping about in a half case..Only real way is to check and double/triple check you have everything in the correct place/correct orientation and then join the cases to test it.No need to shove in all the bolts..3-4 in strategic places is all thats needed. Painful thing to have to do and then find it's not right but really, it's the only way,,,and don't force the cases together,,they will be the usual hassle to join but if they seem held up on something don't force the issue..Take the cover back off and recheck things..That'll probably end up making bits on the other case fall out or jar loose from position,,Such is life..Continue with care..

Edited by Horri

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I think I found the problem!

blauw3.jpg

blauw2.jpg

blauw1.jpg

This is the second gear, which is located on the countershaft.

It has been very hot as you can see.. I think the heat deformed the gear, made it a tiny bit bigger..

When I put the cases togheter, this sprocket gets pressed tightly against the second gear on the main shaft, making it hard to turn.

I found it by installing the shafts, with all the gears, in the engine cases, without anything else> still tight.

Then I removed this gear, all of a sudden the shafts spin perfectly.

Hope this solves te problem. Now to find a new countershaft and secondgear.... :banana:

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I think I found the problem!

blauw3.jpg

blauw2.jpg

blauw1.jpg

This is the second gear, which is located on the countershaft.

It has been very hot as you can see.. I think the heat deformed the gear, made it a tiny bit bigger..

When I put the cases togheter, this sprocket gets pressed tightly against the second gear on the main shaft, making it hard to turn.

I found it by installing the shafts, with all the gears, in the engine cases, without anything else> still tight.

Then I removed this gear, all of a sudden the shafts spin perfectly.

Hope this solves te problem. Now to find a new countershaft and secondgear.... :banana:

Does the bushing the gear rides on spin,or is it seized to the shaft,,it`ll need replacing too by the looks of it...

The reason i ask is because the countershaft has an oil hole and so does the bushing,if the bushing doesn`t spin then no oil gets to the gear causing this...i`m thinking a piece of the piston or something got under that bushing,making it stationary then the lack of oil did the damage to the gear..

B

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Does the bushing the gear rides on spin,or is it seized to the shaft,,it`ll need replacing too by the looks of it...

The reason i ask is because the countershaft has an oil hole and so does the bushing,if the bushing doesn`t spin then no oil gets to the gear causing this...i`m thinking a piece of the piston or something got under that bushing,making it stationary then the lack of oil did the damage to the gear..

B

It spins. But if I slide the bushing about 3mm to the right it locks up.

Definitly damaged. I'm going to try and get a new bushing and second gear pair. Hopefully this solves the problem. :banana:

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I checked the partsno's again and guess what I found... These gear pairs differ in years 87,88,89. Sooo I guess one of the previous owners installed a wrong gear in there/ didn't replace them as a pair.

Glad I found it! :banana:

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