|
|
Post by m2736185 on Mar 19, 2011 17:48:45 GMT -5
I am tryin to determine if its worth upgrading my scooters.
I recently purchased a 2000 Eton Beamer with 4k miles on it. Right now it stops at 30 MPH. I figure If I get a new CDI it will not limit the revs and I will be able to get up to 35 MPH.
Now, will an expansion chamber and rejetting my carb get me an extra 5-10 MPH?
|
|
|
|
Post by 90GTVert on Mar 19, 2011 18:13:02 GMT -5
The new CDI and a tuneup could have you at 40 at least I'd think, unless you're very heavy or something. Make sure the carb has a proper main jet and adjust the CVT if needed. Might just be a wire to clip on the CDI rather than replacing it.
The expansion chamber should get you around 5MPH I'd hope. You will likely need to upjet. You will probably also need some stiffer clutch springs and possibly lighter roller weights to make up for the low end you lose with a tuned pipe.
I put a 70cc sport kit on a Beamer last summer for someone. It was already de-restricted, and even with me at close to 300lbs it would do 50MPH. I tuned the carb, swapped roller weights, because whoever installed them had put them in way too light. It could pick the front wheel up just a hair with the lighter weights, but they were too light for best speeds. The BBK costs less than a good pipe, and you see gains in accel and speed. I always suggest BBK before pipe.
|
|
|
|
Post by m2736185 on Mar 19, 2011 22:52:27 GMT -5
|
|
|
|
Post by lshigham on Mar 20, 2011 5:20:58 GMT -5
Big Bore Kit. Usually 70cc.
Yes, either of those CDI's will do the trick, if it is rev limited.
|
|
|
|
Post by 90GTVert on Mar 20, 2011 5:26:28 GMT -5
Maybe I should have said tune the CVT rather than adjust. But yes, you can swap weights and springs to change clutch engagement and the RPM that you accelerate and cruise at.
|
|
|
|
Post by lshigham on Mar 20, 2011 5:45:02 GMT -5
Maybe I should have said tune the CDI rather than adjust. But yes, you can swap weights and springs to change clutch engagement and the RPM that you accelerate and cruise at. Brent means CVT, not CDI  |
|
|
|
Post by 90GTVert on Mar 20, 2011 5:48:59 GMT -5
Yeah. Sorry. I woke up, turned on the PC, and answered that. Sometimes that's a mistake. lol Edited.
|
|
|
|
Post by reveeen on Mar 20, 2011 7:02:34 GMT -5
I gotta wonder, 10 years, and 4k miles, how close you are to rebuild time anyway?
Personally, I consider anytime between 4k and 6k, rebuild time (on a small 2 cycle operated at "the pin").
I have one that "needs", one "due", and one "unknown". A summer of rebuilding here it seems.
It would be a bit of a shame to spend the time (and money) tuning only to have the engine expire shortly after.
|
|
|
|
Post by motorhead on Mar 20, 2011 8:22:07 GMT -5
Its mileage, not age that ages a machine. A lot of people have a misconception about used scooters because when their weedwacker or mower gets a few seasons of use they throw it's poor peforming @$$ out. This throw out the mower mentality worked it's way into scooters somehow. I can tell you first hand, 4K on a scooter is nothing. They are built to do 20k of commuting. All your scoot needs, is a good carb and air filter cleaning, a new CVT belt and the tire pressure brought up to spec. Also, the old mower gets into a shop where its tuned back up, de-grassed and guess what, gosh darn it, it runs like new again. I wonder why??? I've come across both 80's and 90's scoots with more miles than yours that run great. The Minarelli engine design is tried and true and has got to be in the top 10 motorcycle engines of all time. It's been put in everything and has a 50+ year pedigree. A faulty minarelli with 4k miles is not a reflection on the scooter, but a sign that the rider abused it. I don't care if its a chinese minarelli or not. The engine design is SOLID, plain and simple. If people treated their cars like they treated their scooter, cars would only go 6k. www.minarelli.com/motominarellieng.html |
|
|
|
Post by shakerdriver on Mar 20, 2011 9:20:06 GMT -5
my wife had an 02 yamaha vino that had 13800 miles on it when we finally sold it and it was still running. it was a minarelli, so that 4k doesn't mean a whole lot of nothing if its still going good. we sold the vino because it was gonna be more expensive to replace the broken plastics then it was for another scoot. so don't let the miles factor that much into your modding decisions.
|
|
|
|
Post by reveeen on Mar 21, 2011 10:43:24 GMT -5
Sorry fellas......... I'm not convinced: that it is not a good idea to pull the jug off of an unknown engine, for a "look-see", before trying to make some power out of it.
Who knows the actual mileage, treatment of, and general condition of, something purchased "used"? Do you spend $200 on a pipe, transmission mods, and odds and ends, blind, on a 2 cycle scooter that won't break 30mph?
Chances are it's just rollers and belt, maybe a carb clean-up, but what if it's not?
So, sure, check the rollers and belt, clean up the carb, but before going any further investigate what exactly you have there.
|
|
wolf
Scoot Junior
Posts: 5
|
Post by wolf on Mar 29, 2011 20:57:49 GMT -5
I bought a SYM Jet Euro 50 and i'm trying to do what i can to tune it without buying expensive parts. Any suggestions??
|
|
|
|
Post by stepthrutuner on Mar 29, 2011 23:25:32 GMT -5
You're going to have to pull the jug to do much. There's a nice ceramic coating on your Sym's cylinder bore it should give long service if taken care of. I suggest matching exh. flange opening to pipe and perhaps opening up the diameters there just a tiny bit. Eliminating the resonate tube coming off of the headpipe (crimp or weld patch) if so equipped. Smooth the openings of the transfer ports and boost ports on the underside of the cylinder.... especially eliminate the ridge that exists on the ports' inner sides where they meet the cylinder's spigot or skirt if you will. If your cylinder gasket is 0.5 mm add another one (get two new ones) and take that much (or a couple of tenths more) away from the head gasket thickness (or possibly eliminate the gasket). Match up your cylinder gasket(s) (eliminate any overhang). Eliminate any mismatches in the intake/reed cage area. Go freer flowing on the intake (there are freer flowing stock filter replacement elements from Malossi, Poloni, etc. Play with the main jet to get the best seat of the pants feel with the best plug color.
You can advance the timing by moving the pickup sensor at the ignition rotor too.
Details in the Tech Section here
|
|
|
|
Post by m2736185 on Mar 31, 2011 1:50:28 GMT -5
So I decided to just have someone work on the scooter for me. So far they rejet the carbs main jet to an 85...put on an expansion chamber, new cdi and they said it will do fifty. They told me stock the rollers are prolly thirty. What do u guys recommend for speed and accelerAtion? 10 grams?
|
|
|
|
Post by 90GTVert on Mar 31, 2011 5:47:59 GMT -5
Stock the rollers are somewhere between 4 to 8 grams. It would do nothing but bog if they were 30g. You'll probably get the best results with around 4g and they should add a set of later engaging clutch springs to offset the loss in low end power from the addition of the pipe.
|
|
