Fred Head Questions

[HumanPerson]

JBWeld works wonders

 

[HumanPerson]

It's Christmas time. I'll send you one of those steel sleeved cylinders with the transfers already corrected with JBWeld.

I have 2, other than the one on the bike as it sits.

Over $1,100.00 worth of items for only $300.00 for you young Yeti

 

[HumanPerson]

Just messin with ya Yeti Friend!

I'd probably cry if i really got rid of my gas bike

 

[HumanPerson]

For what it's worth........ I'm Proud of you Yeti

 

[YetiWoodz]

So is this porting method good for the intake?

How about the exhaust? Same thing pretty much?

 

[Wrench]

Your welcome, anytime!

This is what I get if you added 2mm of JB-Weld to the roof.

View attachment 102010

JB-Weld works wonders and will not come off during operation if properly prepped. Don't expect it to last an entire cylinder life but a couple years of use atleast till it softens ever so slightly. Surface preparation is key as aluminum as some know oxidizes readily due to free oxygen. All surface's must be shiny and free of dark oxidation via filing. Then must be washed in acetone and kept in a film or vat of the stuff while the JB-weld is mixed. Upon ready to use the JB-Weld is when acetone should be wiped away, so its only momentary exposed to oxygen to gain the best bond.

Fixing the side wall flow as mentioned is a huge improvement all across in torque, I do it to all my cylinders via dremel and file.
This is a cheap stock cylinder with 150/110 that I'm working on. Top side is exhaust, there usually is a big slag pool there, combined with the square transfer edge it tends to just spray out in any direction. The intake side is 1mm higher then the exhaust and sloped. Mimicking your cylinder style of directing the transfer flow more elegantly.

View attachment 102011

Running water throught the transfers and oberving the flow is a ok way to see how the fuel/air might flow.

Also for ring life while your at it chamfers help on the port edges.

5 min JB Weld or 24 Hr JB Weld? There's a big difference. 24Hr will last longer in high temps.
5 min is for temps of 350*F and 24 Hr is for temps of 600*F Or close to that I don't remember the exact temps
I would suggest 24Hr JB Weld

 

[YetiWoodz]

Good point. @Wrench
24h "Original" formula JB-Weld should be used.
The kwikweld stuff gives off the smell of regular 5 min epoxy.

@YetiWoodz
It's not going to work in the exhaust port but it does work also in the intake but last's much longer.
The intake can be filled slightly to improve velocity on stock manifold and carb or to offset case on a reed build.
If your build a custom p/p instake and get a larger carb the inlet can be enlarged.
Intake port can pretty much be left alone for most circumstances as the mean area is about twice as big as the carb. When it should be the same or about 10%

Oh ok, I thought porting was for any build, but makes sense if its for bigger carbs so that velocity isn't lost in inlet.

 

[Street Ryderz]

I have a steel walled cylinder. I want to port it for more power if I can.
View attachment 102001
View attachment 102002
The ports are already a little bigger than the stock cylinder. Can I still go bigger? And do you agree with this guys porting?
View attachment 102000

The raised area on the bottom of the port is not good and will most likely snag the ring! It should be flat or just slightly radiused opposite the top.

 

[Medic]

Redirect the exhaust side to flow towards the intake side, @Street Ryderz explained that to me so really that was a big positive mod.

I figured out how to do the mod on open transfers with no JB weld.
What do you think?

 

[Street Ryderz]

I figured out how to do the mod on open transfers with no JB weld.
What do you think?

Looks good, that's my preferred method been doing it that way for years now and don't have to worry about epoxy failing.