Triumphrat

dorkingbonny

I have a 1970 T120. The book says rear chain 3/4 inch play while rider seated - this is very difficult to measure - what should it be when on centre stand?

How do you guys get the wheels aligned?

Desperate to get it finished!

Cheers

Mark

oilyboot

If I'm -sure- the frame and swingarm are both straight, I simply measure from center of the rear axel to center of the swingarm bolt. When both sides are equal, the wheels -should- be aligned.
This method works well, providing nothing is bent or badly worn.

On an unknown bike, I use the 'two straightedge' or string method when checking alignment for the first time, then check and note the C to C axel/swingarm measurement for future reference.

Here's a nice description the string method: (disregard the "y word")
http://www.yamahafz1oa.com/sportryde...ntmethod.shtml

The straightedge method is the same routine, using two 8' long perfectly straight pieces of most anything in place of the string.


Chain play on centerstand will vary a bit according to rider weight and shocks. Try 1 1/2"-1 3/4" to start, then check under load and adjust accordingly.

You'll need a helper. A nubile redhead is my personal favorite.

jimballard

1 3/4 inches of free play on the centerstand works just fine. I've used it for years with no problems.

Better too loose than too tight: Jim

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KADUTZ

Anybody got the part number on the redhead?

OzBloke

Thought of making a rear wheel alignment jig recently, until I asked DAGAD (legendary dude he is) look over the plans for me.

His method is much simpler, and I've adapted it a bit to locally available bits.

A length of 3/8" threaded rod about 20" long, with 4 nuts and 4 washers. Bent 2 x 4" lengths of steel wire into an eye at one end, to go on the rod, and a straight pointer (sharpened) at the other.

Use nuts and washer to secure one eye pointer at the very end of the rod. Set the other one near the other end, but do not tighten. Parts cost me $6.



Centre punch both ends of the the swing arm axle and the rear wheel axle. Put the fixed pointer on the swing arm axle centre piont, and adjust the free-moving end to the centre of the rear axle. Adjust till both sides are the same.

Jim's spot on with the chain play.

Hope this helps.

Pete

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OzBloke

Hey Kadutz & Oilyboot, I think the part number for that redhead is something like 38-2436, but I think you want the DD upgrade version.

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GrandPaulZ

I always adjust mine to be "just taut" at the point where the countershaft sprocket, swingarm and rear axle are in a straight line (you must sit on the bike and compress the shocks to get there), but you have already received excellent advice in the replies before this one.

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DAGAD

Hey guys, can this red head with DD upgrade be bought on this forum or do I have to look elsewhere. Sounds expensive to me! High maintenance? Thanks for the compliment, OzBloke.
Roy.

[ This message was edited by: DAGAD on 2006-04-17 06:56 ]

Gale_Gorman

Don't use a measurement with a load on the bike. When you hit a big dip or bump and bottom out, your chain will be supporting the bike.

On the centerstand, at the midpoint of the chain pull down moderately and the push up measuring the difference and adjust till it's 1 3/4".

For a whole lot of years I have used two lightweight steel angles, one on each side. The angles are 4" x 3" x 14ga steel x 7'-0" long. I drilled two 1/4" holes spaced enough so I can use two 1/4" x 6" bolts to clamp the rear wheel between the two angles. If the front tire is the same width as the rear, the alignment is done when the two bolts are snug-tight. Two of my bikes have a front tire 1" narrower than the rear so I have two strips of wood 1/2" thick to space between the angles and the front tire.

This arrangement holds the wheels in perfect alignment while I adjust the chain and then tighten the rear axle.

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okiecityflash

It seems like my '95 harley (belt drive) shop manual, which I never had to use, checked alignment like our good friend Dagad. Measuring from the swing arm shaft to the rear wheel axle shaft. I don't know how I forgot that. Too much whiskey under the bridge I guess. Used to bend a wire coat hanger on each end.

[ This message was edited by: okiecityflash on 2006-04-18 21:05 ]