[Ruyguy]

Those thansfers bridges are there for a reason , to support rings and also helps increase velocity in the transfer by making to separate channels vs 1 big sluggish one.

 

[Atvrunner2]

I have cut those fingers out before and worked fine. Another thing is I have some old TM and Sanren 44mm heads, they didnt use the fingers like the newer ZK or other currently manufactured cylinders.

 

[Chrisi]

You can use bigger port area with splitted transfer ports. Also the gas flow and direction of the gas can be better with splitted transfers.

 

[MrKitty]

I thin them down a little bit but don't remove them they support the rings and lower the friction.

 

[Ruyguy]

I have cut those fingers out before and worked fine. Another thing is I have some old TM and Sanren 44mm heads, they didnt use the fingers like the newer ZK or other currently manufactured cylinders.

Have you noticed any difference between having them and not having them?

 

[Atvrunner2]

Other than more power no. But they had more work done, I haven't tried just that mod alone. Maybe I will. To be fair, I haven't owned any of the running ones long even to see wear or a top end rebuild. But I still have one more cylinder that is not on a motor yet. We shall see.

 

[Atvrunner2]

Here is a Saren (left, top first pic) and older TM 44mm cylinder heads. No split, the base is the same size as a split cylinder however the top is a little smaller on the open transfers vs the split transfers.
Eventually these will be worked over and used. The Saren is new but the TM was on an engine but not a lot of use.

 

[MrKitty]

I can say this for a fact if you try to run chromoly rings and you don't have the split transfer Port the rings will just shatter but chromoly chainsaw rings are 1.5 mm wide wear pocket bike piston rings are 2 mm wide.

 

[Atvrunner2]

I honestly wouldnt run chromoly, but I guess that is preference. Stock works just fine.

 

[Ruyguy]

I thin them down a little bit but don't remove them they support the rings and lower the friction.

Have any examples of thinned down transfer bridges? Like along the base all the way to the top thinner or just cut down to match bdc?

 

[Atvrunner2]

I don't have any examples but I remember reading on here a few people did thin out the fingers. As far as I know it worked fine. I have a few older 44mm cylinders with no fingers, one brand is Sanren

 

[Ruyguy]

I don't have any examples but I remember reading on here a few people did thin out the fingers. As far as I know it worked fine. I have a few older 44mm cylinders with no fingers, one brand is Sanren

On one hand i completely agree removing the fingers makes more volume so lets more charge in but im wondering if with the fingers the charge just gets a higher pressure and velocity by passing through the fingers , and thinning out the fingers would have me afraid about having messed up the angle on distribution through the combustion chanber , like why did they add fingers if your better off just taking them off lol

 

[MrKitty]

If you're running boost ports leave the fingers it will make the engine last a lot longer it also helps the function of boost ports causing a pressure differential.

If you're not running boost ports go ahead and carve them out.


I strongly suggest you try it with them in first it's very easy to take the cylinder out and remove them and then you will get an idea of the gains in torque that you get by leaving them.

 

[Ruyguy]

If you're running boost ports leave the fingers it will make the engine last a lot longer it also helps the function of boost ports causing a pressure differential.

If you're not running boost ports go ahead and carve them out.


I strongly suggest you try it with them in first it's very easy to take the cylinder out and remove them and then you will get an idea of the gains in torque that you get by leaving them.

Absolutely

 

[kray15]

just a thought. When ADA originally produced these kits back in the day (2005-2007 era) they didn't have the split ports. China then copied their kits. The split ports started to show up in the chinese head kits around 2015 or so. And back then we would try to look for the head kits that didn't have the split ports. I don't think the cag motor is efficient or powerful enough to benefit from having them. We used to remove them when porting.

 

[Ruyguy]

just a thought. When ADA originally produced these kits back in the day (2005-2007 era) they didn't have the split ports. China then copied their kits. The split ports started to show up in the chinese head kits around 2015 or so. And back then we would try to look for the head kits that didn't have the split ports. I don't think the cag motor is efficient or powerful enough to benefit from having them. We used to remove them when porting.

I opened up my original minicross motor and its actually a 44mm lol and also with no split ports, ( has that decompression notch too that i heard isnt that good, but anyway after measuring the stock width of the ports on each cylinder the split one is not only deeper on one side but is also wider by a full 4mm at the base , which more than compensates the split, that said you could still remove them , bigger ports yes but will you sacrifice port velocity by doimg so?

 

[Atvrunner2]

I dont believe so, you are still limited by what is actually coming in through the carb.
Also many of the old timers on here widened the older non split transfer ports. So they were probably just as close.

 

[kray15]

This is very useful

Make Your Head Kit Work Correctly!!!

So, As most of you guys know...I can't seem to keep my hands off of Cag heads! This is a great little post to answer a few questions that seem to come up often about chinese made "ported" head kits. A few members on here asked me if i could take a look at their head kit that they recently...

www.pocketbikeplanet.com

 

[MrKitty]

Basically what it boils down to is engine longevity if you leave the fingers in and just thin it down your rings will last way way longer because they don't have to hop that huge ledge.

There is a point where bigger bigger bigger ports are not going to help anything at all because the real restriction is the engine charging through the crankshaft and if a full circle crank is your fancy it will effectively make the charging problem worse.

I get the most power gains from tightening up the squish ( effectively raising the compression ) you have to be careful when laping the two-piece head kit that you don't go too far around .25 - .27 is where it almost takes two people to start the bike one person to hold the bike down and the other person pulls it with a leather glove or oven mitt! ( Make sure you replace the wrist pin bearing every five or six tanks 😉) replace the pull start string with a BMX brake cable or snowmobile pull start cord 😂

50:1 Amsoil dominator 20% paint thinner 92 octane ( ethanol free ) 1oz octane booster ( I use the Lucas oil booster for off-road use only )

 

[kray15]

I agree with what you're saying about fcc's. They take up needed crank volume and are more then often unbalanced. They aren't really beneficial. Smoother crank bearings are a better choice.

I once went real strict with my squish and ended up ruining about 4 aluminum pull starts. From that I found out the plastic pull starts were better because they would flex more and not just crack like the aluminum ones did. I also started going a little looser on my squish because it was such a pain to start.