Need to sustain a liitle more power? By kczukiman (Read 2,381 times)

[kczukiman]

I have a new BMS V9 150cc.It is not completly broke in yet with only 225 miles on it.I am happy with the top end but would like to sustain more power going up grades.I am thinking of changing out clutch and torque springs as well as putting 10g or 12g sliders from scappydogs.Any ideas if Im heading in the right direction?
Thaks,Dave
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[kczukiman]

Thanx for the reply.I do not have a tach as of yet but will sure get one.I also have not yet checked my roller weights.Guess I better get to work lol.Yea a few hills but nutn like you got.

[kczukiman]

By the way,does the 150's fire every stroke or every 2nd stroke?

Also is it safe to change to a uni filter type air cleaner with out changing the exhaust to a larger diameter? I shore do read a lot of horror stories from people that cant seem to get the correct jet combo/air fuel mixture correct.

[jhbietz]

Dr Jr has you pointed in the right direction. The only thing I can add is if you do change your torque spring change it bephore you start playing with the weights otherwise your get to do it again as the spring changes your "shift" points and often requires heavier weights.

[kczukiman]

Great info thanx fellers.Will start on it this week

[kczukiman]

Ok,I have a set of 10g 11g and 12g rollers,and I have a set of 1500 rpm clutch springs/and torque spring. I still have yet to get my tach. That wil be next. My next question is how much plastic do I have to remove on my BMS to take off the variator cover?

[zugzug]

You dont have to remove any. Just pop the passenger peg out and remove the 2 screws near it. That will let the plastic flex out enough to get the cover out from behind it.
-Zug

[ce]

It's prolly a long case with those 12 inch wheels, so look for 10 bolts. They're different sizes, so punch holes in a piece of cardboard and stick the bolts in the same pattern they are on the cover.

[gmoney]

One suggestion is to remove the crappy emission controls. If your Evo is like my Carino, it has a PVC valve that has two vacuum lines twinned together from the manifold which terminates in what looks like the end of a sprinkler. Remove that and connect your fuel pump vacuum line to one of the now open vacuum ports on the manifold. Connect the other vacuum line to the line which had your vacuum fuel pump. You'll notice and immediate improvement in startup and idle as well as better fuel delivery. I left the line going to the canister from the fuel tank since I wanted to be sure the tank was vented. It doesn't seem to help top end speed but it sure improves drivability and cold starting.

Gary

[kczukiman]

Thanks for all the input.I will heed all advice.Great info.

[kczukiman]

Ok,I tore into it tonight after work. After having it apart I changed out the clutch and torque springs to the 1500 rpm ones.Also I checked my stock variator rollers and they are 17g.I alternated them with 11 g rollers.I took a quick little run around the hood and it defiantly has better pick up speed.0-30 is very smooth and quick.After that she climbs slower.Be for top speed was around 52-55 me being around 230 . I still needs to tackle the vacuum lines.
My belt seems to be very sloppy.Its an 835 20 30. When moving it up and down has about 3 to 5 inches of variance.Seems to sloppy to me any feedback would be appreciated.

[kczukiman]

Ok bone head move on my part,I orderd wrong clutch springs.I orderd 50cc 2 stroke springs instead of 150cc. Torque spring is correct so I changed back my stock clutch springs until my new ones arrive. Also orderd a gates belt tonite.

[ce]

Excellent, excellent.

But you need to wrap this work up, and get started on that carburetor. It probably has a 35 pilot with a 105 main jet, or maybe a 108, or a 110. You just don't know til you open it.

What you want is a 115, big old stream of fuel, gushing in there at WOT, and maybe a 38 pilot jet. It'll bring up the power.

Just drain the fuel bowl, disconnect the hose, the fuel inlet hose, and some vacuum lines if they get in the way. Loosen the clamps, work the carb loose, flip it over and use your best screwdriver to take off the fuel bowl, unscrew the jets, see what you've got and upjet accordingly.

[kczukiman]

Aug 10, 2010 12:40:15 GMT -6 gmoney said:

One suggestion is to remove the crappy emission controls. If your Evo is like my Carino, it has a PVC valve that has two vacuum lines twinned together from the manifold which terminates in what looks like the end of a sprinkler. Remove that and connect your fuel pump vacuum line to one of the now open vacuum ports on the manifold. Connect the other vacuum line to the line which had your vacuum fuel pump. You'll notice and immediate improvement in startup and idle as well as better fuel delivery. I left the line going to the canister from the fuel tank since I wanted to be sure the tank was vented. It doesn't seem to help top end speed but it sure improves drivability and cold starting.

Gary

I removed that crap you are talking about.One thing I noticed is that the fuel vacuum line is bigger diameter then the intake on the manifold.Do I change out the vacuum hose to a smaller diameter ?

[kczukiman]

I completed my destruction of unwanted emissins crap. Worked great.thanx for the advise.I also orderd my tach today.
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I will be trying a 17g / 10 g roller combo next.

What really has me puzzled is Running 17g/11g combo I hit 55mph wich I couldnt do running straight 17's? Would it be because of the new 1500 rpm torque spring ?
UPDATE:Tried the 17/10 didnt like at all.Didnt seem to be as effective as the 17/11. I seem to get good take off but wouldnt hold power as well.So for now I like 17/11.