My real question

[stilh036prohog]

When porting saws do you guys get or upgrade the carb for more flow?

 

[Ted Jenkins]

No. How much flow are you after. 2 3 4 5 10% or more. Often one carburetor is used for many models so a small increase in flow is that a small increase in flow. Performance gains are realized elsewhere. As previously discussed is how efficient can the muffler be made along with the cylinder changes. Thanks

 

[cus_deluxe]

carb mods on many saws can make noticeable gains. not all require it, but some do to reach full potential. not at all an uncommon practice to drill seat/main jet etc to provide more fuel. not uncommon to thin shafts/clean up casting defects in venturi

 

[blsnelling]

Sometimes, but it's not required.

 

[Ted Jenkins]

Cus what is full potential? Most small motors I worked on could run up to 24,000 RPM putting out up to 10 times factory recommended output, but seemed a little impracticable. I think a understandable approach to what are the parameters as to how far will one go to gain a increase in performance. Thanks

 

[cus_deluxe]

. I think a understandable approach to what are the parameters as to how far will one go to gain a increase in performance. Thanks

i dont think thats even a sentence...its pretty simple ted. some saws the stock carburetor will feed enough fuel, even after the saw is ported. some carbs do not feed enough fuel to the saw after port work.

 

[cus_deluxe]

Most small motors I worked on could run up to 24,000 RPM putting out up to 10 times factory recommended output, but seemed a little impracticable.

and what the hell does that have to do with the conversation. and impracticable is not the right word. it is indeed possible to carry out carb mods, so wtf are you even talking about?

 

[stilh036prohog]

What it was a simple question.

 

[cus_deluxe]

haha, you got a couple relatively simple answers, and then one that made no sense. brad said it about as well as it can be said.

 

[stilh036prohog]

Yea the first post was funny.

 

[NSEric]

On the Chinese saws I've ported , the 45-62cc Zenoah clones, the bigger carb/intake makes more difference than porting everything else. This is not the norm tho, these have small carbs stock, most saws have big enough carbs stock and gains from adding a larger one will be minimal.

 

[Brent Nowell]

carb mods on many saws can make noticeable gains. not all require it, but some do to reach full potential. not at all an uncommon practice to drill seat/main jet etc to provide more fuel. not uncommon to thin shafts/clean up casting defects in venturi

Can you elaborate on this process?

I would love to know how to improve a carb, particularly the part about re drilling and changing components. Where do you even get a new main jet? Do you salvage it from an older carb that has a big one?
I have yet to find an online retailer that deals in just small engine carbs and parts. Particularly a walbro dealer

 

[cus_deluxe]

im not a wizard by any means, and theres a hell of a lot more that goes into it than i know anything about lol.

 

[stilh036prohog]

A 028 Super carb on a regular 28?

 

[Huskybill]

I think the only mod with the most to gain after porting is the muffler mod.

If there was more room height wise a switch to a mikuni carb would be a gain. More parts to change during tuning. Slide cutouts, needle jet, needles, main and pilot jets. Been there on the bikes. I put a 40 mm carb on a 2t 390 cr husky replacing the 38 mm carb. After some rejetting the bike wasn’t for a beginner.