SBP Pipe good first upgrade?

SD moto man

SD moto man

New Member
Hey Everyone,

I have a stock 66cc DAX mounted in a Schwin cruiser and it runs pretty good. WOT I can hit about 28 on the flat. I want to increase the top end as well as acceleration. I see a lot of great reviews about the SBP xchamber. Would this be a good first upgrade to my bike, or should I try something else? To get more top end I was thinking maybe a smaller sprocket, I have a 44T right now. And for the low to mid range I could tune the pipe for the right power I want. Also, is there a difference in the black SBP x chamber or the chrome one besides looks? The chrome is $12 more, is that extra price just for show? Would a carb upgrade be more appropriate for the first mod? Any input is much appreciated.

Thanks
 
HI,

In your quest for speed, the biggest thing holding you back (even w/ a stock engine) is the 44T rear sprocket....Without a smaller rear sprocket a tuned pipe or other power mods won't help a lot since you will be basically RPM limited (a stock engine can pull the bike around pretty well but you can only rev the engine so fast before she blows so excess power with low (big rear sprocket) gearing isn't going to help a lot on the top end.

I would recommend a smaller sprocket first (and if you KNOW you are going for power upgrades in the future), go even smaller than you would otherwise without the power mods.

Hope this helps you,

Andrew

PS - How small you should go depends on a number of factors...rider weight, terrain, altitude, anticipated / desired cruise speed, wheel size etc....with more info a good guess as to what the rear sprocket should be could be made.
 
I've got similar curiosities, but I've also got to replace my cylinder gasket and see how my bike behaves then.

I've got a stock 48 cc BGF straight head, 41 tooth rear sprocket, somewhat hilly terrain (some are moderately steep, but not very long. Peddling in top gear is sufficient to keep speed fairly high), I weigh 140-ish pounds, and I'm at low elevation (only around 3-4 hundred feet), and I got clocked by my friend's scooter's speedometer at 32 MPH, but I don't know how accurate that is.
 
Carb, driven sprocket and exhaust are all in need of replacement. Heck whole back wheel and a disc mount drive if you can afford it.
 
1st performance upgrade eh?
I recommend an SBP complete hardware kit, then think about upgrading the power and performance. There is no sense in beefing up the power first with fancy parts when the factory hardware cannot stand up to factory power.
 
If you want good top end first invest in a good carb most likely a DAX RT carb or a good NTcarb some have had good luck with a CNSver2 I had nothing but trouble with mine so I got the DAX, and second I would recommend then getting the SBPpipe nothing different about the two just one is chrome and one is black, and then for the sprocket your stock settings with a 36T sprocket will get you up to around 34MPH or so but with the listed upgrades you get to anywhere from 36-45MPH depending on how the upgrades are tuned. And with a the stock 44T sprocket with the upgrades you can hit about 34MPH. But I strongly suggest before beefing up your bike make sure you have excellent brakes and tires, not the cheap coaster brake if yours has one make sure have at least linear brakes and good quality tires not the coaster tires they don't have much grip, believe me you want good handling on your bike when going over 30MPH. It never hurts to be safe but it will hurt if your not, know what I mean, despite what my signature says.
 
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GearNut said:
1st performance upgrade eh?
I recommend an SBP complete hardware kit, then think about upgrading the power and performance. There is no sense in beefing up the power first with fancy parts when the factory hardware cannot stand up to factory power.
Click to expand...

When you say "complete hardware kit" are you referring to this?
 
I'm sure dax's china girls will hold up fine. I bought a 66cc china girl from Daemonbikes and haven't had a problem with the studs coming loose. No reason to replace when there's nothing wrong with the parts. If their tight, they'll hold for atleast a few years. I bought the sbp xchamber and it runs great. Just gotta get it welded together. but overall its great. 41 sprocket would be great for on the flats and in hils/mountains. I stick with the 44 for the torque to get down dirtroads.
 
@Gearnut&Spaz, the hardware kit really sharpens the look with the allen bolts, and the real steel mount/exh/int/ studs help with not worrying when the mount bolts will snap. If anyone grabs that, they should opt for the Head Stud Kit too. Just that much more piece of mind. (just make sure you get the right threads, it's explained how to check)


About the Xpipe vs sprocket, a smaller sprocket does help even with a stock engine, it just takes a while to get to top speed. Mostly it depends on the hills in your area and/or what type of riding you'll be doing. (But I'm guessing your cruiser won't be offroad much) Oh, and how much pedal assist you need to get off the line :p I'd say go for the sprocket first too, then when you do get an Xpipe you'll get to your top speed alot faster.
 
DuctTapedGoat said:
Carb - Speed Improvement
Exhaust - Speed Improvement
Sprocket - Speed Improvement
Disc Mount Drive - Reliability Improvement
Click to expand...

right on, thanks. apparently I am about to have my hands full. the micargi mustang is beginning to sound like a real pain from some of these fellas. maybe a mistake, first bike and all, but I like a good challenge.
 
SD moto man said:
Hey Everyone,

I have a stock 66cc DAX mounted in a Schwin cruiser and it runs pretty good. WOT I can hit about 28 on the flat. I want to increase the top end as well as acceleration. I see a lot of great reviews about the SBP xchamber. Would this be a good first upgrade to my bike, or should I try something else? To get more top end I was thinking maybe a smaller sprocket, I have a 44T right now. And for the low to mid range I could tune the pipe for the right power I want. Also, is there a difference in the black SBP x chamber or the chrome one besides looks? The chrome is $12 more, is that extra price just for show? Would a carb upgrade be more appropriate for the first mod? Any input is much appreciated.

Thanks
Click to expand...
Well, did youi ever come to a configuration conclusion? seems to me like the fellas are saying smaller sprocket for sure on top speed, and a carb & expansion chamber will do the trick. heard bad things on the CNS carbs, Venice says best to just "aerate" the stock air filter with a few new holes. I diod read that the longer the header pipe BEFORE the expansion chamber will garner more low end power, while a shorter header pipe will give more on the top end.
So in my conclusion, keep shortening until it over revvs and blows up if your heart desires, but a big sprocket will limit the speed, like staying in first gear in a datsun with the pedal to the floor.
I'm curious because I have a heavy bike and I'm 200 lbs. I live in Hilly santa monica/ Venice and need torque. the mustang is a long bike, so I copied VMB and mounted engine as far rear as possible for weight balance and control. plus rear wheel traction.
Anyhow, sounds like a stock carb with drilled out holes in filter cover, a #68 jet, needle at lowest detent for leaner non-rich mixture (they come set super rich) a 36 tooth sprocket on a HD set of wheels, brakes and tires, and an expansion chamber with plenty of headpipe for low end to counter act the loss of the 44t stock sprocket. wheew! lotta words. sorry. keep on rollin. and post some more pictures for us!
 
I didn't notice much of a performance increase with my upgraded pipe and air filter. I did have to lean it out a bit and it runs smoother. There is a little less low and about the same top end, with decent mid range power. It sounds pretty cool too. Not sure if it was worth $100. I need to get the pipe welded and then see if that changed it at all.
 

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SD moto man said:
I didn't notice much of a performance increase with my upgraded pipe and air filter. I did have to lean it out a bit and it runs smoother. There is a little less low and about the same top end, with decent mid range power. It sounds pretty cool too. Not sure if it was worth $100. I need to get the pipe welded and then see if that changed it at all.
Click to expand...

So put simply, the Xchamber just took away low-end, and is a waste of money. Is that your conclusion? I wonder if SBP has a response to this...

I'm guessing theyd say spend more time tuning the carb?
 
SD moto man said:
I didn't notice much of a performance increase with my upgraded pipe and air filter. I did have to lean it out a bit and it runs smoother. There is a little less low and about the same top end, with decent mid range power. It sounds pretty cool too. Not sure if it was worth $100. I need to get the pipe welded and then see if that changed it at all.
Click to expand...

Also, VMB told me that reinstalling the stock air filter, crazy as it sounds, will bring on more power with that Xchamber. just drill some holes...
 
Good to note about the stock filter, I will give it a shot. If you are considering getting the pipe and are on the fence about it, I would say pass on it. If you have the extra cash and really want it, then go for it. I've tried every setting on my c clip with my stock 70 main jet and have it set on the leanest setting right now for the best performance. I have a smaller 67 jet to try, but I think it's already on the lean side and don't want to risk seizing it up. My plug color is a greyish color right now, and I think it should be a little more brown-grey to be safe, so I'm not going to lean it out any more. I was fooled by all the good reviews about the SBP xchamber on their website. Some people claim they got 7mph increase- yeah maybe if they didn't have air in their tires before, I don't see how that's possible. All in all, I think I would be happier with the $100 back in my pocket but at least it looks and sounds cool so it's not a total waste of money.
 
If your engine 4strokes at any rpm then you can lean out the carb more, don't worry about seizing it if you have a good oil mixture you'll be fine. And with my Xchamber I can say really, I got another 7MPH out of it. Before I could top out at about 29-30, after the Xchamber, a cop here in town clocked me at 37MPH. So yes it does work just make sure you don't have any exhaust leaks otherwise it won't work properly.
 
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