Does too much chain dogleg rob power?

[deaner]

Just geared my XM up a bit to 21/49 and 106 link chain is pretty doglegged. Is it worth trading my new chain in for a 104 link or does it matter? Just a pain in the butt. Closest dealer is an hour and a bit away.

 

[retiredpop]

The laws of physics says it will rob power. As to how much that's anyone's guess. Do you have access to a gearing - chain length chart for that sled? A 104 pitch chain may be too short even if it looks like a 106 has what appears to be excess slack.

 

[CUSO]

As it was stated, it might..

I think chain life/ longevity would be a bigger factor...

Think of it.. the more the chain has to bend, the worse off...

But on the other side of the coin, it"s the slack side and the energy to pull the chain with a finger and thumb is minimum and not really measurable.

 

[oler1234]

Deaner don't you run a turbo? Power shouldn't really be a concern right

will a 104 work your gearing... Yes. Lilduke had a thread going, look there for details.

as for efficiency... Well why would guys go out of there way to reduce dogleg or get ride of a tensioner, because it does increase efficiency. Every time those links have to move, it's costing more efficiency. Just another piece causing unnecessary friction, parasitic drag. As well the drag on the tensionor. As well energy/momentum... The weight of that section of chain having to change direction at speed will cost power expenantionally.

cons to such a setup.... Well pulling the secondary is a PIA. There is little to no slack.

is it worth changing, well that's your call. Some of us are nuty over certain things that others don't think is a concern.

 

[pfi572]

If you do enough small improvements they add up and make a difference .
That's why I bet older1234's sled will stand out in performance over others .

 

[deaner]

Thanks for the feedback. Its a pain but Im going to trade the 106 in for a 104 while everything is apart. Yeah I guess the power loss isnt the huge issue, more the added stress on everything.

 

[oler1234]

That's a good point as well. Some places I go you need the ol reverse trick going down hill. That tensionor was never designed to be run in that direction

 

[Modman]

Thanks for the feedback. Its a pain but Im going to trade the 106 in for a 104 while everything is apart. Yeah I guess the power loss isnt the huge issue, more the added stress on everything.

good call, run as tight as possible. Those chains do flex and links do break, the less curves they have to go around when doing 60mph track speeds the better. In addition to all the benefits above, it will also reduce harmonic vibrations in your driveline and chassis, as the chain and roller do vibrate against one another.

 

[oler1234]

Just a thought Deaner, but why buy an expensive 104 chain. Why not go back the stock 51 bottom sprocket, most likely have kicking around, and just get a cheaper top 22 top gear. It will work with your stock 106 chain and drastically reduce the dog leg you currently have.

 

[deaner]

Just a thought Deaner, but why buy an expensive 104 chain. Why not go back the stock 51 bottom sprocket, most likely have kicking around, and just get a cheaper top 22 top gear. It will work with your stock 106 chain and drastically reduce the dog leg you currently have.

I already bought the new chain so it will just be a straight exchange. Reason I went with the 49 tooth bottom to replace my 51 was to gear up a bit, and Maeirch had a brand new takeoff 49 tooth he gave me a deal on. I just thought 21/51 on 7 tooth drivers was way too low of gearing for a turbo. Hopefully it doesnt create too much clutch heat. If I find it does I can always go down to a 20 tooth on top.

 

[kennyblatz]

I wouldnt see a dog leg in the slack side of a chain as an issue while trying to turn a 70lb chunk of rubber.

 

[deaner]

Well I put a 104 link on with 21/49 gearing and there is ZERO dogleg. Looks like Olers picture.

 

[oler1234]

Well I put a 104 link on with 21/49 gearing and there is ZERO dogleg. Looks like Olers picture.

I am gonna guess there is a little slack in it. There are other combos that work with 102, 104, and 106 chains. Pretty much as efficient as it gets with a chain, I would venture to say almost at belt territory with more than half the cost.

 

[deaner]

I am gonna guess there is a little slack in it. There are other combos that work with 102, 104, and 106 chains. Pretty much as efficient as it gets with a chain, I would venture to say almost at belt territory with more than half the cost.

Very very little. If the chain was broken in and that snug I would feel comfortable without a tensioner. I put mine in there anyways but it is not really doing much at this point. Will probably snug her up a bit after the chain stretches out a bit. It can be a bugger to get the gears on with the chain that snug.