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snowangler 02-21-2012 10:12 AM

Indy 500 power
 
I have a question pertaining to how much power a 89 indy 500 should have. The sled has tons of snap up to 50-60 mph, but after that doesnt have much. It tops out around 70 and I still have throttle left. When pulling my portable fish house I can only get 50 mph and again I still have tons of throttle. Is this a clutching issue??

stagesrt4 02-21-2012 10:43 AM

i assume L/C?

snowangler 02-21-2012 11:45 AM

Quote:

Originally Posted by stagesrt4 (Post 120185)
i assume L/C?


Liquid cooled is correct.

stagesrt4 02-21-2012 11:52 AM

Belt

Clutching

Needle settings

Slide adjustment

Etc.....

Gotmud 02-21-2012 12:00 PM

^^??? He has all of them problems? ???:bitchdrama:



Snowangler, your sled should have about 80hp on the conservative side. You should see 90 mph wound out but it should get to 55-60 pretty damn quick. Is this a sled you just recently starting having problems with? I would pull your secondary clutch apart and make sure the spring isn't broken, that would make it shift way early and just bog at wot at higher speeds.

Rubi 02-21-2012 12:02 PM

What do you mean you still have tons of throttle? What's your RPM and speed when you give it full throttle?

Gotmud 02-21-2012 12:05 PM

A broken secondary spring would take off normal then it would get stuck in high gear. You could be going 60 with half throttle and go to hammer down for it to only bog because it can't backshift.

I guess I just assume that is what he means by, "I can only get 50 mph and again I still have tons of throttle"?

Rubi 02-21-2012 12:19 PM

Sounds like a secondary clutch problem to me too.

snowangler 02-21-2012 01:16 PM

Quote:

Originally Posted by Gotmud (Post 120199)
A broken secondary spring would take off normal then it would get stuck in high gear. You could be going 60 with half throttle and go to hammer down for it to only bog because it can't backshift.

I guess I just assume that is what he means by, "I can only get 50 mph and again I still have tons of throttle"?

I got the sled at the end of last season and didnt have the chance to ride it and this year we have had ZERO snow. So I havent hade an opportunity to open er up till this weekend. It doesnt really bog as much as it takes awhile to pick up speed after 50ish (maybe considered bogging?). But I am thinking thats what is going on, a broken secondary spring. I typically give everything a try.. Is this a huge pain to rip apart? Is there pullers involved? ???

Gotmud 02-21-2012 01:23 PM

No pullers required and actually pretty easy, just kind of intimidating is all. Since the machine is new to you I'm going to assume there is nothing wrong with the machine other than 25 yr old clutch parts. Personally, I'd replace the primary and secondary springs. You might as well replace the helix buttons while you are inside the secondary, seeing as they are also probably 25 years old. Inspect the primary clutch weights for wear, same as the helix in the secondary. I'm sure that would make a huge improvement for you.

DirtylilWolfess 02-21-2012 01:50 PM

While I agree with all the other Nutz about the clutching (you're probably quite due for some clutch maintenance, I am left wondering why you need to pull a fish-house faster than 50mph.

I have one of those unbeatable machines such as yours, and am pretty impressed with just how lively they get with proper springs and tuning.

snowangler 02-21-2012 02:26 PM

What color spring would you all recommend that I go with?

I dont necessarily need to go faster than 50. It just wouldnt allow me to if I wanted to beat the next guy to the fishing spot!!

mmgg 02-22-2012 12:15 AM

Change your primary spring and at least clean your secondary if you if you can't afford bolth ,it'll feel like a new sled.
stock springs are good.

make sure your belt is adj. correctly
Gear it down a tooth,,if you want a faster towing speed

Gotmud 02-22-2012 07:39 AM

Yes stock springs are sufficient, especially if your just pulling a shanty with it.:thumbss:

snowangler 02-22-2012 10:50 AM

Quote:

Originally Posted by mmgg (Post 120234)
make sure your belt is adj. correctly
Gear it down a tooth,,if you want a faster towing speed

If you cant tell. I am pretty new to the snowmobile world.... and now for the 20 questions game.
When you say belt adjustment? Is it the same as alignment? And, to gear it down a tooth, I asssume that would be in the primary? Would it make a dramatic difference to gear it down a tooth since I am not always towing or is it easy enough to switch between teeth? Thanks in advance!

OCR 02-22-2012 10:58 AM

No, he would be referring to changing the top sprocket in the chain case to one with one less tooth on it. Swapping back and forth from this would not be easy to do on the trail or even on the trailer.

This would drop the top speed by appx 5 mph but would allow the engine to remain at a higher rpm so it would tow a load easier.

Checking primary to secondary alignment will improve power transfer efficiency as will making sure that all the components of the drive train are in good working order [no binding/worn bearings].

blue avenger 02-22-2012 03:05 PM

Almost any time you are not using all your top speed you will benefit from dropping the gearing to get more felt power to the ground. Measure your belt with also, if it is worn thin, it will effect your clutch working properly. As they run $60- plus it is likely you have a worn belt adding to things.

SnowMO 02-24-2012 11:11 AM

I have a Question about the spring in the secondary Clutch on the helix. There are four holes to place the spring in to, I changed the hole it was on to a different one now it seams so much more quicker off Acceleration. What is the difference and does it affect performance or top speed?

OCR 02-24-2012 12:05 PM

It also will affect peak rpm.
Too high and you will notice that it appears flat at WOT, too low and it will feel as if it is straining to reach it's peak but just can't make it.
Peak rpm would be 7800 on that engine.

Rubi 01-27-2016 01:05 AM

Quote:

Originally Posted by SnowMO (Post 120321)
I have a Question about the spring in the secondary Clutch on the helix. There are four holes to place the spring in to, I changed the hole it was on to a different one now it seams so much more quicker off Acceleration. What is the difference and does it affect performance or top speed?

I don't remember for sure which direction to move the spring to achieve it, but moving the spring to a different hole changes the preload on the torsional movement of the spring. A tighter preload will slow down the upshift, so the sled will build RPM more quickly. At the top end, a tighter adjustment adds RPM. Moving four holes will add approximately 250 RPM at the top.

When you reassemble the clutch, remember to preload the spring before you install the snap ring. The back, or moveable sheave, needs to move 1/4 turn counter clockwise before you push the helix down to get the snapring in. Just use common sense to figure out which hole in the helix puts more pre-tension on the spring. I haven't had a button clutch apart for quite awhile, so I don't exactly remember how things line up in there. All I remember is that if you don't preload the spring correctly performance is terrible.


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