GasGas 50SM Q:

[slocalspode]

I know the GasGas EC50SM is kind of a rare bird here in the USA. I am
hopping someone might have the answer to my question.
I am trying to find out who makes the motor for the GasGas 50cc bikes.
Is it GasGas? Or Minerelli, Piaggio, Polini. I know it is not the same motor
that I have in my Derbi Senda 50SM.
A friend of mine has the bike and we have been unable to find a "Big Bore"
kit for it. I know GasGas makes cylinders and pistons for their 65cc MX
and 80cc trials bikes. And I think they used to make a 70cc trials cylinder too.
I would assume the trials cylinder port timming would not be "sporty" enough
for a street SuperMoto like the EC50SM. Am I wrong? Is the high RPM
performance gained from the pipe used, or the port timming. If so. Would the
top end from the TXT80 fit the bottom of the SM50 motor? Or is there an
aftermarket performance kit available for these bikes? Like a Hebo or
Malossi or MK.
Thanks for any clues to my search.
Jeff in So. Cal.

[barkeater]

I believe that Rising Sun has 70cc kits for the 50's. If it's the same as the EC50 boy, it's based on the trials mini TXT50 boy. The pre-05 EC/SM 50's ARE the trials bike with a subframe welded on.

Give them a call and see if they can help you. If I remember right, they said the 70 kit made the 50 into a cool toy for fat old men.

Don't quote me on this, but I think the motor is a Minerelli design, the bottom end is Minerelli and the top end is designed by Gas Gas, but cast in Italy by a sub-contractor.

The Gas Gas 50's are REALLY an exotic European bike if there ever was one. From my experience with the pre-05 50's, their biggest weakness is an undersized radiator and poorly located fender that impedes airflow through the microscopic radiator. In 05 they started making special motors for the EC/MX 50, eventually ditching the water cooled engine for an air cooled one.

Jim Snell at Rising Sun has all kinds of hop up tricks for the TXT/EC 50 boy minis.

Hope this helps.

I feel like I should add a disclaimer that this is mostly heresay that I have pieced together since I bought my son a brand new 2003 EC50.

[slocalspode]

Thank you for your thoughts. I'll give Jim a call soon and see what he has to say.
If my memory wasn't so fuzzy from being and old fart. I'd say I talked to Jim
about this a couple years ago....But I could be wrong.
If it is a Minerelli motor. Isn't that the same motor in the Aprilia RS50? the AM6
or AM9 motor? I would think AF1 racing would be able to get a big bore kit for
it.
I'll attach a picture from the GasGas site of the bike I am talking about.
It is a pretty cool little scoot.
looking at the picture. I don't see how this is the same frame as a TXT trials
bike though. Closer to a Pampera maybe.
Cheers and thanks. Jeff

[barkeater]

Ahhh, truly a unique beast. That is based on the EC Rookie and it appears to be a motor based on the 80cc Trials bike. Have you tried GoFasters just for S41ts & Giggles? They have a direct line back to the factory in Spain and usually enjoy a challenge.

Looking at the factory site, it appears I'm all wet on the pre-05 SM 50's. The SM has always been in the Rookie frame, not the mini frame.

Good luck.

This is the bike I'm thinking about:




A considerably different bike.

[Loosenut]

Jeff,
That is the frame that the Pampera uses with minor changes for the trials engine.

Mike

[wouter-gasgas]

Are you talking about a moped or a 2ft dirtbike?



if you are looking for a 70cc moped cilinder you coult check for a Hebo they make cilinders for the engine in the gasgas moped

[slocalspode]

Yes, that is the bike I am looking to find a high performance 70cc-80cc kit for.
Hebo products are rather hard to find here in the USA. If I knew what the
part # of the kit was. Maybe I could order one from someone here.
Thank you, Jeff

[freejack]

Hi all, I just found this site - at last,

I have the EC50 which is pretty much identical to the SM, purchased it at 6 mths old in 2003 for the wife, sold my own bike & started riding hers, at first i hated it (lack of power)but then learned how to ride it (ring its ass every where you go),It would now go down as one of the best bikes ive ever ridden/owned, I have no hesitation riding A & B grade sections on trail rides.
As for the engine first mods to do are cut the expansion chamber in the middle as close to the weld as possible, rip out all the power deadning mesh thats there & weld it up. Next drill the air box & let the thing breath,you might have to check your carb settings to make sure your mixtures are good. Buy the time you have done this you should be good for approx 45 mph depending on your gearing and totally transform the power delivery into something enjoyable.
The motor on these is also used on the Gilera GSM and old Derbi Senda (pre 2000 models).
You will find very little information on them if you go looking for Gas GAS.
I have just put the big bore kit on it & what a difference. Power is very similar to the KTM sx 85 but has smoother more usable delivery.
The one that was recomended to me was the Italian made Malossi or the Gilardoni (Gilardoni cylinders are used as standard) rather than the cheaper Taiwan or China made units.
I went for the Malossi MHR (full race), 21mm pwk carb & bigger inlet manifold.
total cost was around $650.00 nz$ .
Engine number is EBE050
Hope this helps & I haven't waffled on too much , theres some part nos and info below.
Alex

Cylinder Metra Kit Pro race Derbi 70cc
(# 65199)
race set-up. 18-20 Horse Power is reachable! Fits the EBE050 engine untill
2005
Size : 47,60mm
Brench : Pro Race
Type : Metra kit
Color : Aluminium/ gold
Material : Aluminium
PinSize : Pen 12
Cooling : LC
Volume : 70cc
Fits : Derbi GPR, GPR Nude, GPR Racing, Senda DRD R, Senda DRD SM,
Senda Extreme, Senda Extreme SM, Senda R
Gilera RCR, SMT

Cylinder Hebo Manston Replica Derbi 70cc
(Artnr. HR4000145N)
The Manston Replica cylinders are developed by Hebo and produced by
Athena.
Wide butterfly ports and an aluminium insidehead are the
charasteristics of

Derbi GPR, GPR Nude, GPR Racing, Senda DRD R, Senda DRD SM, Senda
Extreme,
Senda Extreme SM, Senda R
Gilera RCR, SM

MALOSSI

MHR Replica (mid race) 79cc # 31-11693
MHR (full race) 79cc #311985
MHR Team (full worked) 79cc
WWW.malossi.com

[slocalspode]

Now THAT is some information I can sink my teeth into.
I sure hope you are correct. Do you have any links that
confirm that the MHR replica, Hebo etc.. kits for the
Derbi Senda will fit the GasGas SM50?
I purchased the Malossi MHR replica 79cc kit for MY Derbi SendaSM.
I have not installed it yet it is part # 3111693. I got the MetraKit
Pro-Race Thrower exhaust and the Delorto 21mm carb to go with it.
My Derbi is a 2002, so I am not sure the exact same kit will also
fit my friends 2002 GasGas SM50. He is not local to me so I can
not compare them face to face.
If this is true, you have made my day.
Thank you very much.
Welcome aboard the GasGasRiders club. Stick around and answer
as well as ask lots of questions.
Cheers to ya, Jeff in So. Cal.

[freejack]

Hi Jeff, originally when I was looking I had the same run around like you got - it wasn't until I emailed some racers over in Europe that they identified the motor & 2 different people came back with it being the Derbi Senda, etc & Gillera power plants as I couldn't find any reference to GAS GAS. I then got on to scootparts, who has a good variety of suppliers in there catalogue. From what I can see the Kit you have got for the Derbi is the exact one that will fit on the Gassa.
Check out the Malossi site in my previous email.
What sort of money do you pay for the Malossi kits over in the states?

www.scootparts.nl
www.oemparts.eu/default.asp
www.opvoeren.nl/shop/uk/default.asp
www.sip-scootershop.com/

Let me know how you get on.
Alex