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Discussion Starter · #1 ·
I currently am riding a 97 indy 488 supersport and im looking for some mods. I've been looking at some mods but i need some help. Anyone have any ideas for my sled? PLEASE HELP!!
 

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i would suggest gearing and clutching but thats about all i cant think of. It would be tough to find pipes for that sled and if you did find em you might be paying an arm and a leg for them.
 

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I had the 97 Super Sport and here is what I did. 1.) Installed thin head gaskets which raised compression to 143 psi. In doing so, you need to cool the engine, so installed a shield ($3 cooking sheet) between the muffler and fan intake. Also punched open all front vent holes on the cowling (directly behind the bumper). Removed the front bumper. 2.) Bored the carbs. 3.) Grinded weights on primary clutch and installed higher engagement spring. 4.) Re-wound secondary clutch with more tension. 5.) Heat wrapped the exhaust pipe just after the "Y". 6.) Changed gearing from 21-39 to 20-39. By doing steps 1 to 4, your rpms go up considerably. So even though the 20-39 in theory is 5 mph less, the increased rpm of the engine offset the drop in speed and actually moved this sled into the 90+ mph range. A totally different sled once the mods were all done. Also installed plastic skis to lighten up the front end. Have fun! Those are great sleds. BulletProof.
 

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Discussion Starter · #5 ·
I've been looking towards installing new high engagement springs but how did you grind the weights? Is there a certain way that it should be done? Also, how exactly do you change the gear ratios?
 

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Dan-Senior said:
I had the 97 Super Sport and here is what I did. 1.) Installed thin head gaskets which raised compression to 143 psi. In doing so, you need to cool the engine, so installed a shield ($3 cooking sheet) between the muffler and fan intake. Also punched open all front vent holes on the cowling (directly behind the bumper). Removed the front bumper. 2.) Bored the carbs. 3.) Grinded weights on primary clutch and installed higher engagement spring. 4.) Re-wound secondary clutch with more tension. 5.) Heat wrapped the exhaust pipe just after the "Y". 6.) Changed gearing from 21-39 to 20-39. By doing steps 1 to 4, your rpms go up considerably. So even though the 20-39 in theory is 5 mph less, the increased rpm of the engine offset the drop in speed and actually moved this sled into the 90+ mph range. A totally different sled once the mods were all done. Also installed plastic skis to lighten up the front end. Have fun! Those are great sleds. BulletProof.


what kind of head gaskets did you use? were they stainless? i think that a guy could contact cometic gasket and get a set of multi-layer stainless gaskets made for this purpose.... how long did that motor last?
 

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jtb0322 said:
I currently am riding a 97 indy 488 supersport and im looking for some mods. I've been looking at some mods but i need some help. Anyone have any ideas for my sled? PLEASE HELP!!
Keep it cleaned and tuned. Maybe bore it a few over[only if you're already in the state of tear down]. maybe reeds or exhuaust but the minmal gains for the money would not likely be worth it. The best bang for the buck will be in carb jetting and clutching. I have a 488 and they're only designed to do so much. It's an economy sled with reliability in mind. Stay away from ethanol where possible and use fuel treatment if you do use it, and quality plugs and belt make a difference too. I melted two engines in the name of squeezing out performance. These engines are known to be "bullet-proof" but only within certain parameters. Have a REPUTABLE mechanic tune and jet your carbs. Don't mess with 'em unless you really know what your doing. I hope this helps. If you want a real upgrade for not a lot of money trade up to another sled. Say something like an older XLT, XCR, Ultra, or a Storm. They're out there for reasonable prices.
 

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Just ride it how it is, they are great sleds and motors, My dad has had one since new, and it always starts and runs good. Get a good one inch track like a camoplast predator and 96 studs, you will be surprised how much better the traction will be.
 

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jtb0322 said:
What exactly should i do to the clutch? How should i shave the weights?
Don't bother shaving or grinding the weights, your best bet is to just get a new primary spring with a bit more engagement, and a stiffer secondary spring with a more aggressive helix than the stock 34 degree one that they came with, spinning more RPM's is not gonna make it any faster, gearing down will make it a bit slower on top but it will get to top speed quicker, spending money on trying to get more HP out of a 488 fan is like trying to sell a chocolate ice cream cone to a lady with white gloves on a 90 degree day, if you want more power then its time to upgrade to a bigger cc sled or at least move up to a liquid cooled 488 Indy 500, I owned one of these sleds, bought it brand new in the fall of 96, rode it for one season, put 1600 miles on it and the very next spring I snow checked a 98 XC 700 and never looked back, the 488 fans are what they are as explained by a few other posters, its a white bread and butter type of sled, clutch it, jet it (if needed) and ride it.
 

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Discussion Starter · #12 ·
Can anyone tell me what size carbs are on my sled? They are mikuni carbs but i have no idea what size?! PLEASE HELP!
 

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jtb0322 said:
Can anyone tell me what size carbs are on my sled? They are mikuni carbs but i have no idea what size?! PLEASE HELP!
34mm roundslides
 

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Discussion Starter · #14 ·
Would new aluminium intakes with built in filters help by eliminating the airbox and allowing more airflow? How much of a difference would this make?

such as http://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=1874&store=Main&catId=311&productId=p1874&leafCatId=31102
 

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jtb0322 said:
Would new aluminium intakes with built in filters help by eliminating the airbox and allowing more airflow? How much of a difference would this make?
No benefits there either, putting air filters on in place of the stock air box will just cause more problems than its worth, especially on that sled, we've already pretty much explained what you can do to make it perform better, clutching,jetting and possibly gearing, anything other than that your just wasting your time,mind and money.
 

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Discussion Starter · #16 ·
What about a fuel Atomizer?

such as http://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=172133&store=&catId=413&productId=p172133&leafCatId=41303
 

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Dude,

Its a fan cooled sled. You could put 1 grand of parts into it and see minimal results. If you want to go like a bat outta hell get a liquid. I should know first hand....I have a 440 super sport and a sx700. I have 5200 miles on the 440 and she ALWAYS starts right up. Great sled. Just leave it stock...its cheaper that way[thumb]. I just rebuilt the primary and secondary over the summer. All new weights, pins, springs etc. Cant wait to RIDE!!!
 

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Discussion Starter · #18 ·
I dont have the money to buy a new sled!! Im just looking for some upgrades for around $100. Could someone plese just tell me whether these fuel atomizers will work on my 34mm Mikuni carbs? http://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=172133&store=&catId=413&productId=p172133&leafCatId=41303
 

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Do a search on tubulators....it's nothing but a snake oil scheme. I read a post from popular mechanics on the tornado atomizer and it was horible. Loss in hp and less mi per gallon highway and city.

Here's a comment I found regarding your info request:

The turbulator is nothing but snake oil, wait till one of the little fins breaks off and goes into your engine.... [Disappointed]
 
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