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boring carbs?


jjfizzle51

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yea you can run the same filter.What you bore is the inside through the center.Your gains won't be dramatic but you should notice the differance.I think a pretty good mod for the money.BTW I think that my purchase fo 35mm air strykers have been one of my biggest dissapointments as far as cost to perfomance.My buddy who has my old bored stock carbs runs right with me.Both bikes are set up with same porting also.

Don't be fooled by all the big carb hoopla,on a dune port engine the stock carb can be made to run damm good!

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yea you can run the same filter.What you bore is the inside through the center.Your gains won't be dramatic but you should notice the differance.I think a pretty good mod for the money.BTW I think that my purchase fo 35mm air strykers have been one of my biggest dissapointments as far as cost to perfomance.My buddy who has my old bored stock carbs runs right with me.Both bikes are set up with same porting also.

Don't be fooled by all the big carb hoopla,on a dune port engine the stock carb can be made to run damm good!

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Agreed. I just posted about over carbing in the jetting forum. Many people make the assumption that bigger is always better when it comes to carbs, but this isn't always so. A guy I ride with, who happens to work at the local Yamaha shop, built up his wife's Banshee, and turned out 78 RWHP on bored carbs (with quite a bit of other stuff of course). My personal opinion is that you can go a long way on bored stock carbs, but you should definitely consider stepping up if you go to a Cub setup or other extensive stuff.

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Yes, you can use the stock filter...buy why would you want to?

 

You will enjoy a longer lived Banshee with a good aftermarket filter..like a K&N mounted on a ProFlow or other (Modquad?) adapter.

 

Big performance gain?

It should. Depends on a lot of things. I have a set of bored Miks on mine..and the work was done by someone I've had work done by before, I know he does good work, it DOES work and I trust him. Did it make a big difference? Oh yeah! His work is more than making the things bigger. He taper bores the carb, too..in addition to oval boring them to 28s.

 

Will you have to rejet?

You most likely will if your jetting was spot-on before.

 

re: big carbs

 

Probably close to the #1 error in tuning, too much carb....strapping a dominator Holley on a small block bracket car. CAN it work? Yep...if it's in BALANCE with all the other 'stuff'! Probably won't, though.

 

VELOCITY of the charge is important, especially on a 2-smoke. Velocity goes down when size goes up...everything else remaining the same.

 

35mm is darn huge for your average 175cc (1/2 your Banshee). Yes...some 125's (bikes) have 38's..but that's kind of a special case.

Edited by canyncarvr
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VELOCITY of the charge is important, especially on a 2-smoke.  Velocity goes down when size goes up...everything else remaining the same.

 

466596[/snapback]

 

You got er dead on ! "rate of flow" stays the same, only Velocity & Pressure change. velocity goes up pressure goes down, velocity goes down pressure goes up. (haha Physics course i took for my EMT program at NSCC) lol i actually learned something in that course... :confused:

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I've done them for myself and my buddy and I sent a set to BenBB for his RZ conversion, and they all work awsome.

I have pics of the procedure if someone can post them for me. PM me and I will email them.

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Yes, you can use the stock filter...buy why would you want to?

 

You will enjoy a longer lived Banshee with a good aftermarket filter..like a K&N mounted on a ProFlow or other (Modquad?) adapter.

 

Big performance gain?

It should.  Depends on a lot of things.  I have a set of bored Miks on mine..and the work was done by someone I've had work done by before, I know he does good work, it DOES work and I trust him.  Did it make a big difference?  Oh yeah!  His work is more than making the things bigger.  He taper bores the carb, too..in addition to oval boring them to 28s. 

 

Will you have to rejet?

You most likely will if your jetting was spot-on before.

 

re: big carbs

 

Probably close to the #1 error in tuning, too much carb....strapping a dominator Holley on a small block bracket car.  CAN it work?  Yep...if it's in BALANCE with all the other 'stuff'! Probably won't, though.

 

VELOCITY of the charge is important, especially on a 2-smoke.  Velocity goes down when size goes up...everything else remaining the same.

 

35mm is darn huge for your average 175cc (1/2 your Banshee).  Yes...some 125's (bikes) have 38's..but that's kind of a special case.

466596[/snapback]

1. thanks for all the info

2. i have clamp ons

3 the guy im going with does tapers for 5 bucks more thanks for all the info im sold

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Kind of a btw...but, re:

 

'..velocity goes up pressure goes down..'

 

And it's air pressure that makes a carb work.

 

Contrary to commonly held belief, carbs don't suck fuel out of the bowl. Fuel is pushed out of the bowl (into the incoming air stream) when atmospheric pressure is greater than the pressure inside the carb throat.

 

That's what a venturi does..it creates a low(er) pressure than atmospheric, causing fuel to flow from the supply through the various orifices (pilot, needle jet/main jet) of the carb.

 

That's part of why bigger isn't necessarily better, carb-wise.

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