Honda Spree and Elite 50 Forums

OK I bought the 44mm BBK from Taz. Stock intake and exhaust, 90 main jet and 5-0.50" holes in the lid of the stock air box. Starts right up and runs fairly well. Problem occurs around 1/2 throttle. It starts to bog. When I back off the throttle a bit the revs pick up. Spoke to Taz and he recommended a smaller jet. I ordered the 85. Just wanted to get feedback from those who have a experience woth this set up. Am I heading down the right path assuming its a rich main?

Thanks in advance,
Bob

Greetings:

Quoth ThistleB:

When I back off the throttle a bit the revs pick up.

With all due respect to Taz, that sounds more like it's too lean. Closing the throttle a little decreases the Air first, which then matches the fuel flow better, thus Internal Combustion becomes heartier. I'd begin by raising the needle to see if the symptom improves with richer midrange.

Thanks Wheelman. I'll give that a shot I actually lowered the needle in hopes of leaning it out, thinking it was rich. Appreciate the feedback.

I would cover up some of those holes you made in the lid. That why you get the pilot jet use back. Then you can drop the main jet more. You don't want to seize after a wot run . On closed throttle is when most guys seize their motor due to not enough fuel feeding the motor which the pilot jet does from 0to1/2 throttle

Big thanks Wheelman.. Raised the needle and it is substantially better. I now need to locate a larger main.

Greetings:

You're welcome, but Baka-san is correct. Your biggest threat is the Dreaded Off-Throttle Lean-Out.
You can't easily enlarge the Pilot circuit, so plug them holes, Pray when you shut the throttle down.
Good luck!

thistleb wrote:Stock intake and exhaust, 90 main jet and 5-0.50" holes in the lid of the stock air box.

CLOSE THE HOLES! Or find a stock (un-drilled) airbox. It won't go anywhere with those holes in the airbox! After that check the size of the exhaust against the size of the exhaust port. The 90 jet should be maybe OK with the 18mm Keihin, but the 85 will be better. If your exhaust port is larger that the exhaust pipe inlet, performance will suffer. The stock pipe is pretty tiny and may be stifling your BBK. But don't modify the airbox!

JJ Joseph wrote:

thistleb wrote:Stock intake and exhaust, 90 main jet and 5-0.50" holes in the lid of the stock air box.

CLOSE THE HOLES! Or find a stock (un-drilled) airbox. It won't go anywhere with those holes in the airbox! After that check the size of the exhaust against the size of the exhaust port. The 90 jet should be maybe OK with the 18mm Keihin, but the 85 will be better. If your exhaust port is larger that the exhaust pipe inlet, performance will suffer. The stock pipe is pretty tiny and may be stifling your BBK. But don't modify the airbox!

JJ just got done telling Tythescooterguy that there are no aftermarket parts for the spree.

Now, minutes later he is giving advice on how to tune a spree with aftermarket parts.


My spree BBK's always ran best with out the stock air box. I used an uni filter.

Trafficjamz wrote:

JJ Joseph wrote:

thistleb wrote:Stock intake and exhaust, 90 main jet and 5-0.50" holes in the lid of the stock air box.

CLOSE THE HOLES! Or find a stock (un-drilled) airbox. It won't go anywhere with those holes in the airbox! After that check the size of the exhaust against the size of the exhaust port. The 90 jet should be maybe OK with the 18mm Keihin, but the 85 will be better. If your exhaust port is larger that the exhaust pipe inlet, performance will suffer. The stock pipe is pretty tiny and may be stifling your BBK. But don't modify the airbox!

JJ just got done telling Tythescooterguy that there are no aftermarket parts for the spree.

Now, minutes later he is giving advice on how to tune a spree with aftermarket parts.


My spree BBK's always ran best with out the stock air box. I used an uni filter.

I agree with Wheelman, don't listen to JJ. His advise is either half assed or completely wrong. The later seems to be the case this time.

i may bee rong. but when a two stroke is lean dont they run like raped apes. then when it gets two rich they load up and bog out

Correct but they also melt pistons running lean thats why most motocross riders rebuilt there motor after a couple of races

You made my morning after seeing "rong". Lmao!