Upgrades for 400 Sport

[Kook]

What can be done to a '99 Polaris Sport 400 to "jazz it up" a bit? The one I'm looking at is a good runner, but kind of Plain Jane. If it was yours, what would you do to it and where would you find the parts? I've already done some searches for plastics/graphics kits, but haven't found anything... is there an engine upgrade kit for this year?

Thanks guys.

[Dan Tenn]

there are others, but these are what I use.

http://www.denniskirk.com

http://www.hotseatperformance.com/

[Kook]

Thanks Dan, I had already been to dennis kirk and didn't find anything specific to that machine. Hot Seat Performance had a LOT to choose from (except a different color of plastic, that yellow HAS TO GO!).

Thanks for the help.

[Wickedfinger]

Ah, a question near and dear to my heart. Believe it or not, there are quite a few places to go for the Gen III Polarises. http://www.aaenperformance.com/ATV_Home.asp
http://www.hotseatperformance.com/
http://www.hpd-inc.com/
http://rittercycle.com/polaris.htm
FMF, Dynoport, DG as well as others make some performance parts for Polaris as well.
The 37hp, 378cc 2-stroke Fuji motor has ALOT of hidden potential and can be modified to produce over 83 Hp. - which is 46 over stock. The motor is actually a very close copy of the famous Honda 250R motor - just enlarged a bit (so close they actually take the same reeds as well as a few other internal parts). The 1999 model was a transitional model as it was the first year for the new front 8.2" long travel struts, but it still retained the 8.2" rear geometry. It also had a different, lower performance, non reservoir Fox shock then the Scramblers. The best thing about them though is they have to concentric drive system.

Performance wise, there are quite a few things you can do liven them up. The one thing they have over manual clutched machines is you have quite a few variables in performance adjustment with just the clutch settings alone. If you ride in deep woods trails, the stock spring settings via the adjustment tab holes in the secondary clutch sheeve and helix, can be adjusted to give you less top end power and more bottom end snap. If you are on fire roads or the desert - you can adjust it the opposite way. Its kind of like adjusting sprocket sizes on a regular quad or trike to suit your needs - except this controls the transmission and you can also adjust polarises sprockets if you want. Most of the companies I listed offer "Power" packages which include usually a pipe, clutch kit, filter, reeds and sometimes a 38mm carb. Power upgrades on Polarises are always called "Stages" i.e. Stage 1 or Stage 2 performance etc. and they go up to Stage 5. While they are no slouch in stock form, they can be made into a rocketship just by adding a pipe. When you add a pipe though, you usually have to get at least heavier clutch springs to handle the extra horsepower properly. Therefore adding a pipe and adjusting your clutching on a Polaris go hand in hand. The good thing is, the clutches are easy to work on and the springs alone are cheap. I have had two 400L's (a "Stage 2" 1996 400L Sport & a "Stage 1" 2000 Scrambler 400L 2x4) and I have used AAEN's Top End pipe exclusively on both for excellent results. Its good for 10hp over stock and it gives the machine alot more top end power and overrev. There also is a Trail pipe available from them good for 5 hp, but you don't have to change out your stock clutching. As far as clutching goes, like I said before you can control alot of the machines power delivery characteristics through its PVT - you have quite a few choices as well - but - the most popular upgrades also come in a package form. I have used AAEN's kit on my '96 Sport but I went with Hot Seats "hypershift" kit on my '00 Scrammy. It consisted of a stronger primary spring and secondary spring, new weights and a new angled helix. I am probably going to change the helix over to a dual angle one soon though. After that you should change out the stock reed cage with a better flowing one from V-Force, Boyesen or FMF. I use a Boyesen radvalve and its good for another claimed 5 hp. from AAEN (I suspect probably 2 though). Not only will it increase your horsepower, it offers a quicker reving and better breathing engine that helps out all over the powerband. Along with the reed cage I would also invest in a good airfilter. They make all kinds of airbox modifications for the quads - but - I ride in alot of mud and water so I keep my airbox sealed tight on all of my rides. You can get the terrific Mikuni 38mm TMX flatslide carb kit from any of the vendors above and it makes a world of difference in performance. They come with a built in adaptor for fitting into the intake holes and work with the stock choke. They are good for 5 hp and help out all over the powerband. If you add all of the "mods" I listed into one kit, you would be at the top limit of "Stage 1" " bolt on" performance and currently my Scrammy is around 52hp with all of them mounted. "Stage 2" includes head porting and they go up from there with 440 kits, race pipes etc. That being said, "Stage 1" mods will give you a machine that will beat anything stock out there in a 300ft drag race.

Like I said before I usually ride in tight woods type of terrain. With all of these mods, my machine is really more suited to top end and not great for the woods. To combat this, I added a reed block spacer - which gives you more bottom end (or more top end, depending on where in the intake tract you mount it) and I adjusted the clutching to give me more accelleration verses top speed - well just a bit. At this point, I'm pretty happy with the bike and shes almost perfect for the woods - adding the new dual angle helix will make it just right I think. It basically gives the quad a steep transmission angle for the bottom half of accelleration then changes over to a slighter angle that gives the machine good top end. Its supposed to follow the engines power curve. I had one on my '96 and it worked well.

You mentioned graffics kits and looks upgrades - well Polaris is the only maker of plastics right now - but - they make the Gen III fenders and seats in just about any color you want. I put 2004 Scrambler black metalic fenders on my '00 (red). Hot seat currently makes a decal set and I have seen others out there (probably from Factory FX). Hot seat and HPD offer seat covers as well as Hi-Flight. DG, PRM, UMperformance and ProArmor all make various bumpers, guards plates for the Gen III quads.

Well, sorry for the novel, I hope it helps - also - I have a good '99 Scrambler Fox rear shock (with the reservoir) that I can't use that I'll let go for cheap it you buy that thing and want to upgrade the shock thats on there. I also have a used FMF pipe (little rusty) for your year if you want it .... just e-me or PM.

[Kook]

Hey, thanks for all the input wickedfinger! I'll be in touch if I buy this thing.

[Kook]

So will any of the newer plastics fit a '99? Where did you get yours?

[OldSchoolin86]

LOL! It was a moment wickedfinger had waited a long time for........

Hey kook, wickedfinger is by far the resident polaris expert here. If there is a trick for a one he'll know it.

[Wickedfinger]

Yes .... I forgot to mention "Gen III" refers to ALL the Scrambler bodied/framed Polarises (Scramblers, Sports and Trailblazers). I usually get all of my OEM stuff from Ronnies. http://www.ronnies.com/micro.htm.
The colors available are: yellow, red, purple, white, blue metalic and black metalic but you need to know what year machine has what colors in order to order the right color. i.e. 1996/99 Sports were yellow with either purple or red nose pieces - '97/'98 Scrambler 500's were purple and black etc. You can figure it out just by clicking on a years models (i.e. 1999), selecting Sport, TB or Scrambler, then click on fenders and read the description - it usually says "red" or "yellow". Another thing I forgot to mention is the fact that you can greatly improve the overall handling of the machine by replacing the stock, mud oriented AT489 tires with a set of race or sport tires on Aluminum rims. Holeshots work great and are usually available in kit form from everybody for around $200 a set but Razrs work well on them too. The rear rim pattern is unique to Polaris at 4/4, but the front ones are 156/4 and you can interchange Banshees, Raptors, Warrior, Blaster and Mojave rims. I have 22" Holeshot XCT's on Douglas beadlocks on my rear and 23" 489XT's on .190 ITP rim on the front. Handling will improve if you switch to a 22" or 21" tire with a lower profile in the front but it lowers the ride height too much for my taste and you can get hung up alot easier.

[Kook]

Excellent, thanks wicked.

[Kook]

Is there such a thing as a 2X4 to 4X4 conversion or something else you can do to make it 4X4?

[smokinwrench]

I seen a 400 sport running sand drags this weekend in the modified class. All he had was a aftermarket pipe. This machine made several banshees look very slow.

[Wickedfinger]

Is there such a thing as a 2X4 to 4X4 conversion or something else you can do to make it 4X4?

Sure, start collecting Scrambler 4x4 parts from eBay and bolt them on. Its pretty much as simple as that.

[Kook]

Might not be an issue, now I've got a line on a '98 that has 4X4. Can't stand that purple and white though, almost worse than the yellow of the '99!

[Wickedfinger]

Might not be an issue, now I've got a line on a '98 that has 4X4. Can't stand that purple and white though, almost worse than the yellow of the '99!

Well, 4x4 can be a good thing. You will give up a little front suspension travel on the '98 vs the '99 (7.5" vs 8.2") but '98 was the first year for the Concentric drive system and shaft front drive.

[Kook]

So, all things being equal Wicked, would you go w/the '99 2X4 or the '98 4X4?