New carb lost power PLEASE HELP!!!!!

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ejbabin

New Member
Dec 8, 2014
14
0
0
Louisiana
hey guys i recently switched to using a "high performance" carb from bike berry. since i put it on it my bike seems to not be revving as high as it used to. I've read that changing the meet can help but i do not know whats in it or which way to go with jet size. i also have a flex pipe muffle from gas bike and their super charge cdi. I'm mostly trying to get speed up but i would also like some low end torque
 

Chaz

Well-Known Member
Jun 3, 2012
1,004
72
48
Vancouver, British Columbia
I've heard from a member here that those flex moto x pipes are quite restrictive. So maybe when you switched to a bigger carb it just needs higher flow muffler.
 

ejbabin

New Member
Dec 8, 2014
14
0
0
Louisiana
i would think that could be a part issue but the major power loss came when i put the new carb on before i had the exhaust or cdi.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Could you be more specific about what carburetor you have and what you had before?

Those 'buzz words' like Race, Speed, High Performance' High Output are all meant to make you believe they will make you go faster. Often, with the right tuning, jetting, etc, the stock components will work just fine. Always be wary of marketing come-ons.

"Supercharged CDI" ?????????????? :)

Tom
 

ejbabin

New Member
Dec 8, 2014
14
0
0
Louisiana
when i bought it it just said high performance carb but i think its an sha clone carb. i had the stock nt carb on before.

i think i just need to change the jet on the carb but i don't know what size jet is in it or wether i should go bigger or smaller.

the super charger cdi is gas bikes cheaper equivalent to the hd lightning from what i have read on other posts and it seems to work great
 

Davezilla

New Member
Mar 15, 2014
2,705
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San Antonio Texas
I agree with Tom, a lot of ebay sellers use those buzz words to make people think they're getting something better for their engines, and most the time it's just a carb off a different engine and they may or may not add a cool looking air filter then call it a performance or racing carb...
The SHA clones usually work pretty good but they're not all created equally, the genuine Dellorto SHA is definitely the best qualitywise and it does out perform the NT if jetted right. There is one that's even better at pedalchopper.com, it's a SHA clone but it has an idle mixture screw so the idle circuit is adjustable without having to go inside the carb, the carb uses the idle circuit from idle to redline so adjusting the idle mix is an easy way to fine tune once the right main jet is installed.
There's also the Dax RT carb which is another SHA clone that's been reported to work better than the others.

The Supercharged CDI is a copy of the Rocket CDI except it's in a small black housing instead of a pill bottle. They also copied the HD lightning and call it the Thunderbolt cdi, but truth be told, none of the aftermarket CDI units will actually make your bike faster, and in some cases, the stock cdi does out perform a few of the aftermarket ones. I will say the Geniune aftermarket CDI's are known for their reliability, but those who have tested all the different CDI units side by side have reported what the guys who make these didn't want getting out... the lack of any significant performance gain when tested and measured against the stock ones and other aftermarket ones... I'm not saying they don't work, but don't expect a lot of performance gain out of these...

If you want better performance or speed out of your bike, the Fred head only costs $39.95 for the genuine head, and it's a proven performer. The SBP pipe and the Snake pipe are the only aftermarket pipes I'll recommend, they are both modified pocket bike pipes, but the guys who made them actually tested them to be sure you'll know there's a significant difference in performance over stock. Juicemotoparts.com sells some really nice solid copper head and base gaskets and in 2 different thicknesses so you can run a thin head gasket for a little bit better compression, or run a thicker base (or a stack of base gaskets) to raise your cylinder up for better port timing, you need to know what you're doing here tho.
Just simply switching to a 6cc Fred head and one of the pipes I mentioned will make a very noticeable difference in power and torque. I run Fred heads on everything I build, they're cheaper than the clones, but made better and they do perform, there are other good heads out there like the Puch hi hi, the Diamond head from Jake's, and the one from Bicycle Motor Works, these are all really good.
The Snake pipe from Arrow Racing is probably the best pipe for performance, but the SBP pipe from Sick Bike Parts does offer the end user the ability to tune it to their engines which can be a big plus.
The biggest power gains other than a really good pipe come from porting the cylinder, there are a lot of postings on this, and there are a few vendors who will port a cylinder for you, and sellers like Jake's, crmachine.com, and Arrow Racing offer some nice bolt on kits that'll completely change your engine in a good way.
 

skitchfish

Member
Oct 27, 2010
222
0
16
Michigan
Oh my God! They actually say just slap it on and go faster! No adjusting needed. 78mm?Tom hit it right on the head about marketing but this is over the top and nearly criminal!

Sorry to say this does not look good for you EJbabin. Buyer beware
 

skitchfish

Member
Oct 27, 2010
222
0
16
Michigan
EJbabin, If this carburetor has a plastic adapter inside the clamp that attaches to manifold it could possibly or more than likely be leaking and needs to be sealed with a product called seals all.

The fact that it says it's a 78mm carb throat and fixed jet is very confusing to me and maybe another member can clear that up.
 

Giacchina

New Member
Jun 29, 2022
2
1
3
26
hey guys i recently switched to using a "high performance" carb from bike berry. since i put it on it my bike seems to not be revving as high as it used to. I've read that changing the meet can help but i do not know whats in it or which way to go with jet size. i also have a flex pipe muffle from gas bike and their super charge cdi. I'm mostly trying to get speed up but i would also like some low end torque
Had the same exact issue, took the jet needle from my NT carb and used it to replace the needle in the high performance carb and INSTANTLY much better
 
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