SE50 Big Bore Kit Questions

[W8kbrder]

I posted this in Technical but I'm guessing I should have posted in Performance Technical.

This is what I need recommendations on:

1.) Big Bore Kit - Is there a bolt-on application regarding a bigger piston/head that does not require machining and/or custom fabrication to make it work?

2.) What does everyone think of the 51mm Ruima big bore kit as far as ease of installation/performance output?

3.) Do you have to use a bigger carb if you go with the big bore kit (OKO? Klein? What size recommend?)?

4.) Can anyone direct me to a DIY on the 51mm Ruima big bore kit?

5.) If the big bore kit is just a bolt-on application, what other modifications need to go with it in order for it to work at its maximum potential?

6.) Will a stock starter get it started with the big bore installed or does something need to change?


What I've done:

-Swapped stock restricted .68 Main Jet with .88 Main Jet.
-Bored out restricting washer welded inside stock exhaust (where it mates to the head).
-Replaced single throttle cable with "split" cable in order to control Throttle and Oil Pump at same time.
-Replaced restricted Oil Pump with regular SE50 Oil Pump.
-Replaced stock restricted Variator with Prodigy Variator (kept the stock roller weights).
-Replaced Center Clutch Spring with 1.5k spring and the three clutch grabber springs with 2k springs.
-Punched out 2nd plastic tab in stock Airbox.

[tw39515]

edit just re read your post you must have sa50p if you removed second tab from airbox. and you said its a 2001, get the polini corsa or contesta youll love your self for spending the extra dough. also think about going with aftermarket carb due to adjustable pilot jet.

[W8kbrder]

edit just re read your post you must have sa50 if you removed second tab from airbox. and you said its a 2001, get the polini corsa or contesta youll love your self for spending the extra dough. also think about going with aftermarket carb due to adjustable pilot jet.

Apparently I had an SE50p restricted scooter. Had to do some mods to de-restrict it.

So you recommend the polini, corsa, or contesta big bore kit?

What modifications do you need to make in order for it to fit?...or will it just bolt on?

[tw39515]

it should be sa50p if its a 2001, and yes they are bolt on. the spark plug hole on the cooling shroud needs to be widened due to the spark plug hole angle is a little different. yes the polini is much more tolerable to heat.

[eliteguy50]

edit just re read your post you must have sa50 if you removed second tab from airbox. and you said its a 2001, get the polini corsa or contesta youll love your self for spending the extra dough. also think about going with aftermarket carb due to adjustable pilot jet.

Apparently I had an SE50p restricted scooter. Had to do some mods to de-restrict it.

So you recommend the polini, corsa, or contesta big bore kit?

What modifications do you need to make in order for it to fit?...or will it just bolt on?

What country are you in? Here in the USA, we only received the SE50 series in 1987. Other countries received them for longer runs.

[tw39515]

se50 airbox didnt have the second tab to be removed. did it? whats the engine code on the rear trans cover?

[turtle13]

If its the scoot in your avatar, then it looks to be an aero... which in that form was only available in that form from 85 to 87. The SE50/NB50 engine has a few kits available, malossi, polini and CMR the most readily available. The polini kit seems to be the most popular and available through daywot and his ebay store. The CMR kit is available through vtcycles.com, and the malossi kit seems to only be available direct through malossi. All 3 of these kits supposedly work with the stock head, however the malossi kit has a head that is designed especially for their kit. With any of these kits, you will need to re-gear to keep the engine from over revving and burning it up...
If you have have an sa50 engine, disregaurd everything above... like TW said, check the stamping on the tranny cover for the engine code.
With the big bore kit, you do not necissarily need a bigger carb, just upjetting properly for the correct A/F ratio. Having the ability to adjust the pilot jet really is nice though and is mainly only obtainable by switching to a different carb. Just remember, bigger is not always better.

[eliteguy50]

... however the malossi kit has a head that is designed especially for their kit. ...

As an additional purchase that is.

[W8kbrder]

If its the scoot in your avatar, then it looks to be an aero... which in that form was only available in that form from 85 to 87.

No...that was an old picture of me in college jumping my old '87 Yamaha Razz. The scooter I am currently referring to is a 2001 Honda Elite S.

[W8kbrder]

So to clarlify...I have a 2001 Honda Elite S (de-restricted).

So is there any recommendations regarding the 51mm Ruma Big Bore Head? I had someone direct me to Sleepy Scooters. However I just want to make sure I know what all is available and has the easiest installation...

Any other Big Bore Kit recommendations for a 2001 Elite S?

http://sleepyscooters.yolasite.com/perf ... -parts.php

[eliteE85]

go big or go home- do a stroker 100+ cc water cooled monster

[maddog]

Hey Boston, what do you have, come to the rock and meet me, i will blow your punk * mind