rear chain adjustment

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PanScott
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rear chain adjustment

#1

Post by PanScott »

Hello all, I gave up on the V-T cast brake drum and put the chrome repop one back on. The drum looks like the sprocket has never been replaced, I don't know if it's Paughco or another V-T POS. Time to adjust the chain and the difference between the tight spot on the chain and the loosest spot is huge. From barely 1/2" to slapping the chain guard. I have found so many basic things the PO has done wrong that it could be about anything. The trans main drive gear seal is not leaking (hope it has oil) so I don't think I have a main drive gear bearing out. Before I pull the entire primary apart to expose the whole drive, could it be as simple as a worn out chain?
Bigincher
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Re: rear chain adjustment

#2

Post by Bigincher »

Why would you pull the primary apart to expose the whole drive?
If the rear sprocket is worn (do the teeth come to a sharp point? Noticeable wear on the 'pull' side of the teeth?), then the chain is surely also worn. A chain won't just wear to a certain point and stop, it will wear, get loose, you adjust it- it wears, gets loose, you adjust it- on and on until the axle won't go back any farther. Then the take a link out of the chain, move the axle forward, and start all over again.
You can slow that process down dramatically with all new sprockets and chain, but if the sprocket is concentric to the drum- not perfectly centered- you're back where you started.
I don't think any drum/sprockets are perfect, but some are better than others. I bought a Paughco rear drum and it checked out pretty good. Acceptable.
foundationapps
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Re: rear chain adjustment

#3

Post by foundationapps »

I had this very same question 1 year and a half ago. Had a lot of difference between 1/2" slack and major slack. Sprockets looked good, chain was Old, but not particularly a lot of side slop. Went to take a closer look at the front sprocket and notice that the hub was not quite running true. In fact, while it was running, there was a butt ton of wobble in the hub. In the process of learning about this phenomonon, I discovered how to remove the hub and found that they key was not properly seated between the hub and the mainshaft. Removed that, reassembled, didn't have it tight enough (which resulted in removing the clutch plates and reassembling in the desert at night, good story)...

Long story short, once I got the hub wobble hashed out, the chain was adjustable to 1/2" tight to 1" of max slack.

All that to say, check your clutch runout for wobble, AND make sure the front sprocket is running true also.

Respectfully+
Andygears
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Re: rear chain adjustment

#4

Post by Andygears »

I had trouble getting the dowels to seat all the way into the star hub. Could tighten 3 lug bolts but when the other 2 were socked down, the brakes would drag. I snugged the 2 offenders and rode it a bit and they settled in. My drum & dowels were chromed and very tight in this wheel. Use some chalk and mark chain & drum when tight and loose, might be the drum not seated.

My 2 cents
Andygears
PanScott
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Re: rear chain adjustment

#5

Post by PanScott »

Bigincher wrote:Why would you pull the primary apart to expose the whole drive?
Mainly to check the front sprocket, I would also check the wheel and front sprocket alignment. Even though the trans will be moved to adjust front chain it should slide straight fore and aft.
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