What a difference a pipe can make! :-)

[kaintuckdave]

Hey guys, today I took my scoot to my dealer and got an unrestricted exhaust and a larger jet installed. Went from a 70 something jet to an 88. The pipe has none of the octopus stuff on it. WOW, all I wanted was a solid 35 mph and I got it and then some. Haven't been much over 40 mph yet but don't need to for the roads I travel. It's got way better acceleration and get up and go off the line. Two bills well spent, this dawg's happy! ;D

Also took a bunch of pics. If they didn't come out blurry, I'll start a thread and show some DD 50 derestriction techniques.

[hoove]

Congrats on the upgrade. Deresricting on these 2's seems to be the key. I just put a sito+ and 98 main jet on my Stella. It made a significant difference in the acceleration and overall power, and it sounds way cooler too.

[kaintuckdave]

Oh yeah hoove, forgot to say; mine's not really louder, but it do sound meaner!

[jsorvik]

Any idea how the new pipe and larger jet are going to impact your fuel economy? I would love to pick up a little on the top end, but I don't want to significantly hurt my mileage. . .

[kaintuckdave]

Aug 2, 2008 9:38:32 GMT -5 jsorvik said:

Any idea how the new pipe and larger jet are going to impact your fuel economy? I would love to pick up a little on the top end, but I don't want to significantly hurt my mileage. . .

I'll tell you on my next fill up, I've been getting around 95ish mpg. I think it'll even out though, the motor has to have been fighting that restricted exhaust. Just need to fight the temptation to WOT all the time. ;D

[90GTVert]

Wow 95mpg! I've never fought the temptation of WOT on mine to see that sort of gas mileage. I get 60-70mpg with a 70cc (stock ari box and carb jetting), pipe, and a cvt that stays higher in the revs all the time.

[Karl]

I'm with yall. I just de-restricted my wife's Italjet Velocifero (it had a baffle in the exhaust that had to be dremmelled out) and it seems to hit the powerband much sooner. Whereas it used to only see about 35 mph now it gets to 40. I looked for a restrictor shoulder on the variator boss but found none, so I think it was just restricted at the head pipe.

I just picked up a 2s 50cc Strada RX8 and was really impressed with the quality. I'd had a UM XPeed a few years ago and sold it (regretted that), and this one is nearly identical. This one will hit 40 mph as is and I'd like to figure out how to get a little more zip out of it. I'm thinking of a 70cc kit down the road, but I don't want the Tecnigas type pipe, a mistake I made with my XPeed. I like the relative quiet of it and would prefer to zip around in stealth mode

Karl

PS I have no problem getting a better pipe, I'd just want it not to SOUND like a racer.

[90GTVert]

A 70 kit without a pipe is still a great improvement. Without the pipe I lose a little speed up top, but can still cruise 45mph or better on my Triton. Stiffer clutch springs aren't a bad idea with the 70 either, that should really help leaving red lights. You can prob even leave the CVT alone (if you're happy with it now) without a pipe, because you shouldn't need to tune it to higher RPM operation.

[Karl]

Aug 3, 2008 10:02:05 GMT -5 90GTVert said:

A 70 kit without a pipe is still a great improvement. Without the pipe I lose a little speed up top, but can still cruise 45mph or better on my Triton. Stiffer clutch springs aren't a bad idea with the 70 either, that should really help leaving red lights. You can prob even leave the CVT alone (if you're happy with it now) without a pipe, because you shouldn't need to tune it to higher RPM operation.

90,

Have you been happy with your MRP 70cc setup? I checked out your web page and love the blacked-out Triton! Very nice!

The only thing I was thinking about doing to the CVT was to put a little heavier rollers in the variator once I'd do the 70cc kit. My thinking is that with the extra ooomph of the +20cc, it would have enough torque so that it wouldn't have to wind out the engine. Thoughts?

Also, I wouldn't mind an aftermarket pipe but I live in a neighborhood and don't want to annoy the neighbors with something really tinny-sounding.

Did you have to rejet? If so, did the jets come with the 70cc kit?

Karl

[90GTVert]

I've been very happy with my MRP 70. Like I've said to others, it's no Polini Evolution or Stage 6 setup that will have you screaming and doing wheelies, but it's a good reliable kit. It cost just over $100 (I just got the cast iron version, it's also available in aluminum). I kept my stock air box and stock jetting, even with the pipe. I have a 17.5mm carburetor, and I have been told that smaller carburetors will need more work or replacement(the other option for stock carbs is around a 13-14mm I believe).

My Triton came with 4g rollers stock and was capable of 50mph with the forces aligned, so to speak, so I left my rollers stock with great results. It tops out around 55mph, can cruise at 50mph or better with the pipe. I actually added 1500 or 2000 RPM main/torque/contra/whatever you prefer to call it springs to keep the revs up on mine which works great with the pipe and still feels better without it. I would prob leave the CVT alone for what you want. The torque is better, but I doubt you'd be real happy with heavy rollers on it.

I don't know of any tuned pipes that come with quiet mufflers. It's a shame, you don't wanna be without the pipe once you've tried one.

[90GTVert]

Oh, and if you (or anyone) gets a 70 kit that doesn't include a wristpin bearing you may want to consider getting a Wiseco bearing. I've heard the stock wristpin bearing has been known to fail with larger pistons. Mine's a 12mm wrist pin, I don't know if they are made by Wiseco for scoots with 10mm pins. The Wiseco # is B1043.

Since you're interested in the MRP kit...

Here's just how much bigger the cylinder is


Here's the kit and the bearing I mentioned

[kaintuckdave]

Okay, first fill up today after the bigger jet and new exhaust. I went from my 95 mpg down to 78.6 mpg. I have been driving faster this tank but guess that bigger jet is just pouring more gas in. I'll report back next tank too as I'm still doing octane experiments.

[90GTVert]

79mpg still isnt bad, especially since you have been riding harder.

What octane experiments are you conducting?

[Karl]

I agree, that's pretty darn good, Dave!

[kaintuckdave]

I have heard so many octane arguments that make sense and I'm still confused. The last fact I read was that if your compression ratio is below 10:1, regular is fine. My manual states my ratio is 7.1:1 but says to use 90 or better octane. I've also read that the Asian method of determining octane has their 90 octane = to our 87. Anyway, I'm running a tank of regular this time to see what happens. So far, no knocking or anything.

[Karl]

Just remember that low octane fuel burns better and leaves less residue. If you don't notice pre-detonation (ping/knock) running the cheap stuff then run the cheap stuff!

I'm going to try 87 octane next fill up and see.

Good point about Asian octane method. Ours is (R+M)/2. Here's some good info on Wikipedia about octane en.wikipedia.org/wiki/Octane_rating

[kaintuckdave]

Well, you guys might think I'm crazy, but I'll swear my scoot likes regular better than premium. It seems stronger and using less throttle. I also switched from Valvoline to Bel-Ray Si-7 2 stroke oil so as usual, more than one variable to the equation.

PS, really cool octane article Karl!

[Karl]

Not at all, Dave. I had a friend who used to own an old Honda Civic station wagon. If you put premium in it, it ran like crud.

[rallyrrr]

Bet it was the stratfied charge engine with the pre-combustion chamber aka "lean burn technology".

[rallyrrr]

Oops, left out the i in stratified.

[kaintuckdave]

Okay, I got 78 mpg on the 89 octane and this fill up after running regular 87 I got 84 mpg. Also, my rear tire was low on pressure which messed with my mileage in the past. I filled up with regular again, but might try one more tank of 93 after this one just to see what happens.

[w8tlftr]

Yea a performance exhaust usually can add around 8-10 mph more to your top end and add more power, I think I went up 6 sizes in my jet size when I installed my Tecnigas Next muffler, what I didn't know back then was there are restrictors in the pipe , I learned the hard way, but boy what a differance, I since then have done other mods like Malossi cylinder kit better tires, Malossi filter etc upjetted to a 72 jet now in my 17.5 mm Dellorto carb, tops out at about 55mph on the flat with my 245 pound self on it, without gear changes it's running pretty much at it's peak now I couldn't be more pleased, I still have a few things I might do in the future but it's all good.

[symbiot]

Mang all I got was a measly 3 MPH extra on the top end to ~38 MPH. It was still worth it for the extra pop off the line and to be able to hold 30 MPH up a 5% grade hill.