can someone tell me the correct way to set the chain alignment on a rts 250 car.. we have been using a t square and measuring it off chain carrier to the sprockets with the setup blocks init.. is this the right way? im having a problem of throwing chains and im running out of ideas.. squared the axle twice.. thinking maybe i did it wrong the first time.. change the motor plates cause one was bent alittle ...still can feel it in the car.. almost a grinding when i get on the gas hard...checked and repacked the bearings..axles not bent.. that i can tell .. if it is, i cant see it by eye..any more ideas??

Do you have the rear axle spacers assembled correctly? Do you have a RTS rear axle assembly guide?

Usually I just "eye up" the chain/sprockets when I'm blocking the car... If the spacers are all correct, I would say that the w-link isn't set in the right holes... I just measured my rear sprocket and w/ car on the ground (no blocks) it is 5" from the front frame rail upright to the center of the chain/sprocket... Plus or minus a little isn't going to make that much of a difference...

have you replaced any sprockets ? if the chain is streched it wont fit new sprockets very well , it will cause the chain to bind and jump .

Eyeballing the alignment is usually close enough. If you're sure that the chain and sprockets are good and nothing is bent, then I'd check the chain tension. The correct tension depends to some extent on the type of chain tensioner you're using. I have no experience with the old single roller sprint tensioner, so can't help if that's what you're using. With the double block tensioner, 1 1/2 in. slack should get you in the ballpark. With the double roller tensioner we're using, we set the tension at 2 in. with no problems. The tension also depends somewhat on the driver's weight. Our driver weighs approx. 195 lbs. Hope this helps.

Thanks for all the responses. I have to wait and get a new shift cable so i can run the car again , but im hoping i have it fixed? I have new chain and sprockets on there , but i dont run a tensioner.. used to but took it off ... dont run it on any of our cars anymore. the only thing i found is the spacer for the radius rod that hooks to the birdcage was worn which made that bolt alittle loose.. i hoping that may have been causing it. The other thing .. when squaring the axle does it matter which hole the left side radius rod is in? the last time i did it , it was in the bottom.. this time i put it in the middle. but i run it in the bottom hole..

I would put the tensioner back on. I think that might be your problem. How tight do you run the chain? RTS has the block that goes between the chassis and the rear axel. Basically makes it a snap to make sure your rear axel is square. If the chain is hitting the the pie plates, then you have spacers or your w-link in the wrong mounting holes. Hope this helps.

ok.. im ordering the blocks tomorrow for the tensioner.. but.. i really dont think this is going to help.... tonight at practice my dad was flagging and he could see my left rear wheel moving forward when i smack the throttle .. which is when the noise occurs in my rear axle.. checked everything and can not find anyhting loose..any ideas?

What you need to do is put the ride height blocks in, this means removing the torsion stops from the rear torsion arms. Then take the outer chain guide off the sprocket carrier and put 3 or so nuts on with spacers to hold the sprocket tight on the carrier. Put something on the axle to take the place of the wheel, we use pvc pipe, and assemble the rear axle minus the wheels.. So, basically you have the axle nuts and everything tight on the rear axle, the rear axle sitting on the RIDE HEIGHT blocks (not the setup blocks), then take a straight edge from the rear sprocket and get it lined up with the front sprocket by adjusting the W Link heim.

If you say you can see the left rear wheel moving forward when accelerating, there must be something loose or worn in the rear (birdcage bolts, rear axle bearing, torsion bushing, or the bolts that hold it all together), check all of this before trying to get the chain lined up.

If your not running any tensioner, then the chain is too tight, and probably binding the car up in the corners.

My 2 cents,
Curtis Merriman