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Discussion Starter #1
I has a "new to me 1997 Indy 500" It seems fairly non responsive in the low RPM range. Idles not too bad but dogs from throttle input- up to about 4500-6000 RPMs than runs fine @ about 7500RPM. even before clutch engagement tapping the throttle doesn't seem crisp and responsive. The local shop claims they had the carps all apart yesterday and checked the clutches and they still can't seem to find the prob. Occasionally if under load (heavy snow or starting going up a hill) It will bog to a point of not even moving unless I keep the RPM's up. Machine starts 2nd pull and doesn't seem to flood. any help would be appreciated greatly.
 

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I would check the carbs. again myself to be sure,make sure all jets and passages are clean and that floats are set correctly.Then if that doesn't do it go thru your clutches to make sure they are ok also.The dealer could have missed the problem when they had it apart.later rpm
 

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On your secondary clutch, there is a cam with the numbers 1 thru 5 and it is held on by 3 bolts. What you need to do is see where the belt is riding in the secondary clutch, it should be just a little bit above the top of the sheaves, if it is low in there, you will have no bottom end. If it's low, you loosen those 3 bolts, and turn the cam, I forget which way, but when you tighten it back up, drive it a little bit or spin the track then check and see where the belt is sitting.



http://www.bolliger-mabillard.com

I Love B&M Coasters.
 

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Discussion Starter #4
What would be causing the poor responsiveness and crispness before the clutch engages though? I think I may have clutch problems and other problems as well, any Idea on the Engine side of life what could cause the lack of crispness.
 

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Could be alot of things. exesive blowby cuased by bad rings you can check this by taking of exhuast and manifold and looking at the sides of the piston with a flashlight. if the piston is black or has streaks of black its time for new rings.Bad reeds can cuase lack of crispness. air screws set to rich.But i would be willing to bet that most of your troubles stems from your clutch needing retuned.

Vmaxyam
 

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Here is a link to some tech tips I picked up from Erlandson Performance. One of them talks about belt deflection. Hope this helps a little. Not sure on how to adjust your clutch though, check the manual if you have one for your sled.
 

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try this, check the appearence of your plugs after a good ride , keep it out of the bog range. remember what they looked like for comparison later. if you can find some deep snow to put a load on engine run through it at about 1/4 throttle for about 1 min. stop the engine right away without any idleing and check both plugs. if they are wet or carboned up chances are you are adjusted very rich. if the plugs are chalky white you are lean. If the plugs are noticeably different in appearance between each other , then you must adjust accordingly. I left a reply to a Bobby about his older 600 that might help you too
 

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Discussion Starter #9
This sounds like the closest yet.
I am familiar with 2 stroke model airplane they have separate misture screws hi and low. If my plane engine was working like my sled I think That is exactly what it would be. and I would lean out the idle or low mixture and the quick response would be there. How is this achieved on the Mikuni? Does opening the Air screw on the low end jet lean it out? what are these air screws at and how do I get at them. Should I play with them or is there danger of setting low end too lean. On my airplane if i set low end screw too lean it dies when you snap the throttle to it quickly. richen it up a bit until the response is good and quick. if it is too rich it burrbles and bogs when you hit the throttle until the extra fuel is burned off. I had it too a shop, but if feels to me, that they just leaned out the top end mixture. Which I don't think there was any prob. with anyway. It works a little better. but I think it is in the low end. ??????
 

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If you want snappier low-end and midrange, get a pair of UFO's (Ultimate Flow Optimizers) and put in your carbs. Relatively easy to install yourself, and they give you instructions on how to set them up. They are manufactured by Thunder Products (see webpage at http://www.cloudnet.com/~tpi/ufo.htm).

I put a set in my '89 500, and it made a HUGE difference. For a 500, it goes like a raped ape!
 

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Discussion Starter #11
Right On, I tried This yesterday, She jumps off the line now. excellant.. 1 makes it ride out far in the Sheaves, 5 makes it ride low in the sheaves. I found about 2-1/2 or 3 works good. Do you know if this affects the high gear range as well or does it only affect the low gear engagement. I am wondering if I will lose top end speed with this adjusted to a lower gear engagement. Thanks Alot.

On your secondary clutch, there is a cam with the numbers 1 thru 5 and it is held on by 3 bolts. What you need to do is see where the belt is riding in the secondary clutch, it should be just a little bit above the top of the sheaves, if it is low in there, you will have no bottom end. If it's low, you loosen those 3 bolts, and turn the cam, I forget which way, but when you tighten it back up, drive it a little bit or spin the track then check and see where the belt is sitting.



http://www.bolliger-mabillard.com

I Love B&M Coasters.[/quote]
 
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