Lowest rear sprocket tooth count for Bashan Storm?

[JTridesbikes]

Hi All

So several months ago I upgraded my rear sprocket to 42t and I did get a higher top speed but recently I upgraded to a new carb and I lost that top speed. My question is what’s the lowest tooth count I can run in the rear sprocket without running into any problems?

P.S. I’m already running 17t in the front

Thanks

[herbie]

I ran a 17f 40r and I loved it on my Brozz which has the same engine as the Storm. I tried a 39 and it was too tall for the engine. What carb did you upgrade to?

[JTridesbikes]

Originally Posted by herbie

I ran a 17f 40r and I loved it on my Brozz which has the same engine as the Storm. I tried a 39 and it was too tall for the engine. What carb did you upgrade to?

Yea I’ve read that elsewhere about the 39t. I got a JFG Racing PZ30 carb, I bought it off Amazon and it’s surprisingly a great carb.

[herbie]

These little engines are good and reliable but not powerhouses by any means. It should be able to hold 55 to 60mph without too much trouble in stock form. If you are wanting more than that then you may have to do a little more to help with the power like shaving the head down and port and polish, especially the exhaust port. And a less restrictive exhaust pipe also

[TxTaoRider]

Not trying to sound too sarcastic here, but how is changing to a carburetor that made your bike slower, an "upgrade"?

[JerryHawk250]

Originally Posted by TxTaoRider

Not trying to sound too sarcastic here, but how is changing to a carburetor that made your bike slower, an "upgrade"?

I was thinking the same thing. Spend a little more time in fine tuning the carb. A perfectly tuned carb can make a world of difference.

[China Rider 27]

You can second and third that. A PZ30 is capable of getting all the power out of that motor in stock form and with most modifications.

[JTridesbikes]

Originally Posted by TxTaoRider

Not trying to sound too sarcastic here, but how is changing to a carburetor that made your bike slower, an "upgrade"?

I lost top speed and gained acceleration, the bike now feels like it’s running a higher rear tooth sprocket count. I spend 3 days tweaking the air mixture and finally got it to where it should be and the bike is much quicker than it was stock. I’m just trying to get back to the top speed I had before the carb work.

[TxTaoRider]

Sometimes they'll accelerate a little better rich as it masks the lean spot that a slide carb without an accelerator pump has, but then they wont make as much power after the air velocity through the carb picks up and the main circuit is able to meter fuel properly.

So what I'm suggesting is going down some on your main jet and live with the compromise, or... spend $40.00 on a pz30b (pumper carb) kit, and use the proper main jet for maximum power, and tune the accelerator for maximum throttle response/acceleration.

Then you can get your top speed back without changing the sprockets.

[Bill Hilly]

I am in the same boat as the others about the carb . If you cant get your new carb to do as well as the old carb then it would pay to use the old carb.

[ChipToothy]

17-44/43T seems to be the best all around gears for 65 mph highway riding, anything higher and 5th can’t maintain itself up the long inclines. Not that the 44T is anything to brag about in that zone but it’s the difference of only getting dropped to 50 mph vs. 35 mph. I constantly wish for a 44.5T .

39T and 42T will get you T-boned in city traffic when turning left in to Chic fil A across 2 lanes of oncoming is already YOLO .