chain stretch/ rear sprocket tweaked

[KStoner]

Is it typical to get alot of stretch out of a new chain in just a few minutes? Also my rear sprocket wobbles approx. 1/16". Is this something to worry about? Everything is brand new and I don't know much about BSR's, except that when you fall off your butt can really hurt.

[BAR-TAB]

make sure you have a sprocket guard.if it comes off and somehow wraps around the axle..............instant, and unexpected brakes

[Mike Bean]

KStoner,

How much chain stretch are you talking about? And how tight do you have the chain on your setup?

I have not noticed any unusual chain stretch myself. I usually setup my chain to have about 1" - 1.5" of up and down movement in the center.

As for your sprocket wobble, you will get a little when using the steel hubs that use set screws but it is nothing you can not run ok with. Just be sure you have your rear sprocket is aligned with your front drive sprocket and have a little slack in the chain as I mentioned above.

What I have done in the past to align my sprockets is to block up the rear so the wheels can turn by hand and then position the rear sprocket as best you can with you eye and then leaving the set screws lose, turn the drive sprocket over a few times in the forward direction and it will usually align the sprockets.

Hope that helped...

Mike Bean

[KStoner]

The chain started with 1/2" movement up and 1/2" down. I haven't measured yet, but it looks like 1" up and 1" down. Plus now when I start to get up to speed the chain starts jerking or catching. I might just tighten it a little bit and see if that will go away.

[Mike Bean]

KStoner,

Do not tighten the chain any more. Maybe give it a 1/4" more play and check your front and rear sprocket alignment.

Are you using a clutch or a TAV? Also is your rear axle on your frame straight and is your engine positioned straight?

A good way to troubleshoot your chain problem is to block up the rear of the frame so the wheels can spin free and run the engine at partial throttle and you can see what is moving and causing the chain to jerk. Be careful the BSR does not vibrate off the blocks or it might take off on you when running it.

The chain may have been damage if it was set to tight from the beginning. I would take the chain off and inspect the links for stiffness and be sure you chain is oiled and not dry.

Let me know what you find..

Mike Bean

[Terry Skinner]

the chain starts jerking or catching.

The symptoms you describe are for a worn sprocket and/or a frozen chain. First thing to do is remove the chain and flex all the links by hand to see if any are rusted or jammed. Next wrap the chain all the way around the sprocket. Does it fit? No slop?? If the chain is bad there will be tight spots and loose spots. If the sprocket is bad it will be loose all the way around. If you decide to change the chain or the sprocket then change both. A bad chain will ruin a new sprocket and a bad sprocket will ruin a new chain. In fact you should change both sprockets while you are at it. When we were drag racing the Kawasaki I could count on at least one chain per meet.

[monkey-1]

Are you sure the engine didnt just slip some and give you some slack??

[Mike Bean]

The symptoms you describe are for a worn sprocket and/or a frozen chain.

Terry,

I believe he just purchase the rear sprocket and chain. Now maybe the drive sprocket was not new. I also think the chain may have been setup way to tight from the start. The chain and sprocket may have been damaged from that.

Just my observation...

Mike

[KStoner]

Alright after recovering from landing on my a$$, I took a good look at the problem. Apparently when I stood the stool up on end and almost took it all the way over, the engine got cocked. One side is about 1/8" farther ahead than the other. I didn't ride more than a half a block after this, cause my butt hurt, so I hope I didn't damage anything. I am going to put some jack bolts on the back of the engine to straighten it out and stop this from ever happening again.
To answer other questions, the clutch is new, the rear sprocket is new and has had a wobble since the day I got it, and the chain appears to be in good condition without any frozen links. Also this problem can not be duplicated without a load on the engine.

[Mike Bean]

KStoner,

Like I said before...with the steel hubs you will always have a small amount of wobble but it will not interfere with the operation on the drive train. I run 40 MPH on my steel hub (I think we use the same one) and no problems.

Realign your engine and rear sprocket and leave 1" - 1 1/2" of up and down slack at the middle point of the chain.

Here is what I did to help with chain tension. I move the engine all the way forward to where the chain was tight and then I turned over the wheels to allow for normal pull. After that add a little more to be sure you have about 1" - 1 1/2" of up and down travel in the middle section of you chain. then tighten down the engine and then check the rear sprocket alignment. I like to block up the rear and loosen the set screw and have the engine turn over the sprocket a bit to try to self align and then tighten them screw up and use some Loctite shortly after if it runs ok.

Mike Bean

[KStoner]

Well apparently the Hillard extreme duty clutch was not extreme enough for all 250lb of me. It appears the jerking was from the clutch not being able to lock up. I should have listened and skipped the clutch and got a TAV.

[Mike Bean]

Well it is good to hear you found the problem. Can you oil the internals of the clutch at all to help with the slipping or is it just a poor design?

If you don't mind me asking, what did you pay for the clutch?

Mike

[KStoner]

The clutch is pretty well glazed over. I tried to clean it up, but it didn't help much. I think the clutch was about $30. Just money down the drain. Hopefully I won't have the problem with the TAV.

[Mike Bean]

KStoner,

There has been other discussion about the cheapie clutches going bad on the forum. Below are is a link to discussions on clutches and TAV's.

http://barflyracers.com/showthread.php?t=443

From what I have read, if you are going to use a clutch you need to spend some money like $150 and up. In that case you might as well go with a TAV for about the same price.

Don't worry about the TAV going out on you. Be sure you get a TAV2. I have used my TAV2 for over a year and I weight 225lbs and I have also had a combined rider weight (father and son) of over 300 lbs and it ran perfect.

The tav's do not have clutch pads that go bad, just a belt that wares out which I have not had to replace yet.

Good Luck!

Mike

[Woodchuckscustoms.com]

Mike you are indeed on the money about the Tav System! But If you go with a good racing clutch for about 200.00 your top end speed will blow your mind:hot: It's all about how fast do ya wanna go and how much money do ya wanna spend.:cheers:

[Mike Bean]

Mike you are indeed on the money about the Tav System! But If you go with a good racing clutch for about 200.00 your top end speed will blow your mind:hot: It's all about how fast do ya wanna go and how much money do ya wanna spend.:cheers:

Woodchuck,

Can you explain how a racing clutch can produce more speed than a tav? From my understanding, the TAV changes gear ratios with speed, with that you would actually get more top end than with a fixed gear ratio using a clutch.

Mike

[Mike Bean]

The clutch is pretty well glazed over. I tried to clean it up, but it didn't help much. I think the clutch was about $30. Just money down the drain. Hopefully I won't have the problem with the TAV.

KStoner,

Can you put some sand paper on the clutch pads to ruff them up?

Mike

[Woodchuckscustoms.com]

The Racing clutch is designed to produce qwicker responce then a Tav. I'm not a super tech on the subject but I have used the cheeta racing clutch with a briggs animal and I didn't even had it wide open had the local police clock me and I got it up to 78MPH,but that felt way to damm fast for me. I will have to check in with the owner of this machine and see if he had it going any faster yet? But anyhow the same clutch on a non-racing motor like the handa clones and tacumsa 6.5hp, motors of this type will NOT PRODUCE THE SAME RESALTS AS A RACING MOTOR COMBINED WITH A RACING CLUTCH COMBO DOES for obveuse reasons.The tav set up with the type of motors we run on our BSR's is the best yet over the cheepie clutches though. But if your looking for real speed ya have to spend the buck to get there.:thumb:

[Mike Bean]

Not to be a pain in the ass, but I still do not understand how the racing clutch is going to make a 6.5HP Briggs top out faster than a TAV.

If the HP and RPM is the same and if one gear ratio changes like on the TAV -vs- a non-changing ratio like a clutch I cannot see how the clutch will provide more speed.

It's like having a 3 speed automatic transmission in a car -vs- a one speed.

Just my .025 cents...

Mike

[Woodchuckscustoms.com]

The racing clutches on a non racing motor will produce about the same speed as a tav. If ya want real speed you will need to combind a racing motor with a racing clutch to get the speed. The tav 2 is only rated for up to 8hp the racing motors I have been using are 10 to 25 hp. or more this is what gives you higher RPM's and top end speed along with the gearing. The Tav is great for going up hills. Racing clutches are made for the track not to good on uneven turain.

[bm1]

On the chain alignment...Take a piece of key stock long enough to reach the clutch sprocket and the rear gear. Lay it along side the clutch sprocket and the rear gear. It should be flat against each other. Another tip on chain tightness. If you have a tight spot in the chain while rolling the rear axle. Do this...... If you are using a two piece sprocket, Leave the chain on, and loosen the nuts that hold the sprocket to the hub. Finger tight will do. Now, roll the rear axle over a few times and this will center the gear. Now Tighten up the sprocket nuts and give the chain about a half inch slack, AND DON"T FORGET THE CHAIN LUBE! Some sprockets are aluminum and the chain is steel. Not a good mix without lube. I use the chain wax sold in motorcycle shops. It's a lot less messy.
Hope this helps.
bm