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What's your poison? Mine is 40:1
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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.
 

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What's your poison? Mine is 40:1
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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.
 

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What's your poison? Mine is 40:1
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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.
 

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What's your poison? Mine is 40:1
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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
 

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What's your poison? Mine is 40:1
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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.
 

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What's your poison? Mine is 40:1
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Agree to disagree. The fingers really don't make a bit of difference. It is an annoying conversation piece at best. They can help rings on one engine but not another.
Are the ports bigger, sure now, they were not when they first came out. They wont be if one ports the nonfingered transfer ports.
Less is always better. Dont port the crap out of it. Dont go crazy with the transfers, don't go too big on the boost port. It all is relative.
In the end these tool based motors only allow so much work before they top off and power desends because too much was done.
A FFC is great for low end power, if you want top end DO NOT use a FFC. They basically are terrible for balance. Only because they are Chinese.
Compression.... I believe Mrkitty meant 0.025-0.027 squish TOO MUCH, yes that is overkill. Said best by boosted306, 0.034-0.036 is best, after break in it will rise and not break your hand on pullstart.
I have NEVER broke a pullstart on a high compression motor, best around 0.038" but I don't pull the thing like I am stealing it.
Run 50:1 with 20% trans fluid replacing the oil. Full synthetic always, not necessarily amsoil and 95 to 100 octane.

Two engines on the shelf pre broke in are best.
I have 7. All different specs, wrote on the box the specs.
In all honest opinion, you dont need to add a boost port.
A good custom exhaust pipe, walbro clone carb wt603t, raise compression, little porting of the transfer ports and exhaust port, rocket key, hp wire mod, reed plate and reed stopper mod, you will be surprised at what that alone can do.
 

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What's your poison? Mine is 40:1
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It looks really good, I only made one flow like yours, most I just touchup a little for a uniform flow, but all my current builds I have been selling.
I freeze the bearings and over bake the case halves, one always goes in easy the other never, my luck anyway. I have an impact socket (upside down) on hand that is even with the outside ring ready to go if influence is needed.
I would slap it together and see how it is after breakin.
As for the ada cage, I wouldn't cut it, at least yet, once thats done you can't go back. 90 deg, hmmm, I would use it normal until after breakin, see how the motor feels after a full tank and then try the 90deg, worth a shot. When a lot of work is done and have better/faster flow you need stiffer reeds (the single anyway) to stop reed flutter. Maybe with 2 you can get away with softer ones, fiberglass or carbon fiber.
 

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What's your poison? Mine is 40:1
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Ha, I have what was almost a junk motor, after major cleanup, installed the bearings, both dropped right in. First time ever. 400 deg for 10min in the oven, overnight freezer bearings, put 2 stroke full syn oil around the bearings and dropped with a socket for straightening. I will make a thread, it was a wreck, just a quick rebuild to resell with parts I had laying around.
 

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What's your poison? Mine is 40:1
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I just informed myself with our local chemical place.
Minimum order of dry ice is 20lbs and you have to order a week in advance , totaling 150$ Cad ,
Then theres liquid nitrogen , 15.75 Per Liter and 36$ to rent the canister… your idea seems like the least expensive way so ill probably just do that. I think my bearings have been in the freezer since i bought them last summer , hope i can find them 😅 . I saw a video where they say to grease all mating surfaces , but in another video the guys goes at them with acetone and does not add grease after, what you think?
I have personally only used 2 stroke oil, a few times I didn't use anything, forgot the oil, never had a problem.
 

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What's your poison? Mine is 40:1
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A new bearing?? I wouldn't have removed it after install. But what number is on the bearing?? Hopefully you didnt crack the case. Check that.
 
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