Performance Upgrades Step By Step And Results

Just to get started I have an 2007 Mountain Lite - MTX and ride off trail and deep powder. My weight which is also a factor in doing this project is a huge factor 285 lbs. with clothes and gear. I will be looking to increase track speed which does translate into top end. The motor is completely stock and will work on those upgrades in the off season. I will start with the clutching and traction department which can be just as significant as motor upgrades.

I installed a Timbersled Mountain Tamer rear skid and cut down a 15" track to 14.25" X 144" X 1.75 Camoplast Back Country this year. After skid and track install I noticed an increase of 300 rpms on the tach. The gearing is 17/41, I did not like the sea level gearing which is 19/41. First I changed the primary spring to Green Gold Green part #90501-607G4 for engagement of 3800 rpms. The stock was Green Yellow Green part #90501-605G7 with engagement of 4100 rpms. This took the jerk out of the throttle for low speed manuvering.

After install of track and skid a noticeable increase in hitting the rev limiter at 12,300-12,400 rpms on trail and off trail at holeshot began. The primary clutch weights are 39.76 grams and are stock part #8DN-17605-30 and will remain. The rivets were steel 13.9 length at 3.6 grams on the inner and outer holes of weight from the sea level kit. I changed the rivets to 17.2 length at 4.5 grams on the inner hole and was getting 12,100-12,200 rpms close to were it was when project started. I fine tuned that to add the 17.2 length 4.5 grams rivet to outter hole on weight.

The target rpm is 11,300 for these sleds at peak power curve. The result of above put it were it needed to be 12,100-11,900 rpms at WOT and down quickly to 11,400 rpms. Then the usable range of rpms was 10,800-11,300 depending where secondary was shifting at on and off trail. All speeds recorded will be off dreameter. The top speed that was recorded was 75 mph on trail, 48 mph off trail powder flat run and 38 mph climbing hill with powder.

The secondary setup on MTX stock is with red spring part #90508-55007 set at B-1, the helix is 37 degree. This is also same spring the Standard, FX, and GT have set at A-1, the helix on these is 39 degree. To understand this the higher the degree the quicker upshift during acceleration. While the lower the degree quicker backshifting during load.

Update: Installed the primary overdrive from Schmidt Brothers and found 77 mph on trail, 50 mph off trail and 38mph climbing. Installed the secondary billet helix and WOW what a difference on low to top end upshifting it flat out gets there. I found top end 80 mph on trail, 56 mph off trail and climbing ? will report later.

The final primary clutch weight setup is done with 2 different results found. The first rivet setup was heavier inner rivet hole and lighter outer rivet hole proved better on top end (5 mph more) with less low to midrange punch. The second rivet setup is lighter inner rivet hole and heavier outer rivet hole proved less top end (5 mph less) better low to midrange punch. The weight of rivets will depend on your type of riding, performance additions and rider weight. The first setup is better for trail and the second setup is better for off trail riding.

The difference in throttle response with the seconday helix overdrive is amazing. Instant snap and lift on sled and is great in the bush and tight stuff for me. I also changed the spark plugs to E3 (part #E3.38) and cleaned the secondary sheave from the thick grease and polished like cannondale27 did http://www.ty4stroke.com/viewtopic.php? ... ight=ulmer . These improvements also are noticable with better throttle response, higher idle and quicker starts.

At this point I beleive all improvements that can be made to clutching and traction have been made. I would conclude with the improvements done it is a totally different fun factor and am very pleased with results. With that being said the sled probably could be geared up to 18 or 19 tooth no problem. With the improvements on the motor side yet to come I will attempt the gearing next year probably.

Awesome!Is very rare to find someone with patience to do things one at a time but that is best way for sure to know what is going on.looking forward to it!

I really like the Overdrive Idea, even if it allows you to run 1 tooth smaller top gear and keep the same top speed it will seem like you bolted on an extra 4hp. Price isn't too bad either for the machining.

I will be getting the Billet Helix that way I can keep my stock one to make changes 1 at a time. Gearing change may also be posibble with overdrive will test as we go. I beleive there is more notice of improvement being done to see if you are taking a step back or not. Helps that the trail and off trail is my back yard and I enjoy tinkering. My goal is to get 82 on dreameter with just track and cluthing changes and then maybe geraring. Once that is aceived then tackle the motor and just changes weights on primary.

The engine mod is gone to be intake, porting, exhaust, top secret keep factory ECU remap from other which will curve timing and fuel. The hope is to get 95-100 hp with ultimate clutching and traction.

Between the two of you, its an amazing encyclopedia of knowledge on these little 4-strokes! Looking forward to reading the results

I had overdrive on both primary and secondary clutches on the Mod sled. We saw 99 MPH on the speedo at Munising(hard Ice road part uphill) with the 18 tooth top gear

That's good to know yam177 of the improvement it made and the 18 tooth info. What mods were done on your sled if you can fill us in thanks.

yam177 said:

I had overdrive on both primary and secondary clutches on the Mod sled. We saw 99 MPH on the speedo at Munising(hard Ice road part uphill) with the 18 tooth top gear

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I am interested in what track you are running and if it is studded. If studded, what stud, stud count and placement.

No offense to you yam177 (actually respect your posts and knowledge of the Phazer) but would offer that you carry a pocket GPS unit with you. Most will give you your highest MPH achieved during a particular run.

I am trying to remember what mine was last year. Errrrrr, 82?

I believe 99 on the speedo like he's saying. I had 96 once, and the only reason i looked down was i heard the rpms wound pretty good and knew i was flying. Down icy rail r-tracks/grade. Bone stock.
Otherwise 91 or 92 mph speedo, but still on good conditions only.

rotax454 said:

yam177 said:

I had overdrive on both primary and secondary clutches on the Mod sled. We saw 99 MPH on the speedo at Munising(hard Ice road part uphill) with the 18 tooth top gear

Click to expand...

I am interested in what track you are running and if it is studded. If studded, what stud, stud count and placement.

No offense to you yam177 (actually respect your posts and knowledge of the Phazer) but would offer that you carry a pocket GPS unit with you. Most will give you your highest MPH achieved during a particular run.

I am trying to remember what mine was last year. Errrrrr, 82?

Click to expand...

That was on the speedo never carried a GPS racing.. stock track 96 power point studs down the center belt v pattern. Mod sled did 99 on the speedo stock sled did 95 on the speedo in same section.

Mod sled is ulmners airbox excell exhats three degree keyway timing PCV with my map(modified ulmner base) Intake pods. Overdrive primary and secondary 42 degree helix.

Runs real well I also wiegh 163. sled also has no reverse


hope this helps

[quote=".

Mod sled is ulmners airbox excell exhats three degree keyway timing PCV with my map(modified ulmner base) Intake pods. Overdrive primary and secondary 42 degree helix.
Runs real well I also wiegh 163. sled also has no reverse
hope this helps[/quote]

Please give us the details on the "three degree keyway timing". Who's is the supplier. What is the benefit.
I had thought that you could alter the timing on each cylinder with the Powercommander unit. Not true?

You can with a extra ignition module.

cannondale27 said:

You can with a extra ignition module.

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only the 07 phazer have the igniton module option

I had the dealership re-weight the clutch for "2000 foot elevation." Stock MTX with the 17/41 gearing here, GPS speed WOT on hardpack (and I'm about 195 buckass naked) showed 72.4? I was starting to wonder if going to a 1.5" or 1.75" track would actually help in the deep and or steep (easier to turn the track, rather than the 2" stock?) Aftermarket pipe is going to be a summer project, can't wait to pick your collective brains on what route to go with there, may tinker some with clutch "kits" as well

updates on teh overdrive kit?