Speed

[Jferdi03]

I'm looking to add some speed. I'm completely new to this kind of thing. How would a new cylinder head add speed? What about an expansion chamber? Smaller sprocket seems straight forward. Does gas/oil ratio affect speed?
How much faster would the same engine go on 26 tires compared to 24? Anything else I should know?
I'm sure these questions have been asked before, but posting a thread is easier to and I rarely see an explanation just a lot of opinions on what is the best out there. Thanks

 

[YetiWoodz]

First major thing you can and should do is change out the jet in the carb. The carbs come jetted rich, so by going down in size it will increase power and won't foul the spark plug so quickly.

Buy a 60-80 nt carb jet kit with every size in between. You can add 5 mph easy. Its also very easy to do. Nt carbs I believe come with a 70 jet and my hp carb came with a 78. It seems around 65 is what most people find is optimal.

Start with a bigger jet and go down. Once you have the right fuel mixture, you won't experience 4 stroking anymore and your spark plug will have a sandy tan color.

4 stroking sounds like when you make a motorboat sound by blowing through your closed lips. It happens intermittently usually around top speed. You'll notice your bike going slower during it.

 

[Street Ryderz]

How would a new cylinder head add speed? It won't ! At best a better chamber design will give a more efficient burn and give more squish area that will allow more power to be made when the rest of the engine is made capable.
What about an expansion chamber? A properly tuned expansion chamber improves cylinder fill within a certain range again to aid in making more power but it doesn't really equate to speed as that is determined by the gear ratio the engine can effectively turn.
How much faster would the same engine go on 26 tires compared to 24? Given the same gearing and engine rpm it would be a few mph faster.