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Discussion Starter #343
So been days. I have been working on other projects for quick sales. Cause that's what I do.
Anyway, worked on the flywheel today. What do you think?? First two are the cut fins, then second two are the cut fins ground down.
Should I ground down the rest a bit?? Thinking back, I believe CAM2 said trim the rest 3/8" . Easy mod for sure so far maybe 15min. Less removable time.
Next need to perfect the reed cage mod. Failed the first attempt and have 2 new ones coming.
 

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So been days. I have been working on other projects for quick sales. Cause that's what I do.
Anyway, worked on the flywheel today. What do you think?? First two are the cut fins, then second two are the cut fins ground down.
Should I ground down the rest a bit?? Thinking back, I believe CAM2 said trim the rest 3/8" . Easy mod for sure so far maybe 15min. Less removable time.
Next need to perfect the reed cage mod. Failed the first attempt and have 2 new ones coming.

The 3/8" finclip mod is for the pistomported fl;ywheels as theyre unlike the reeded engine flywheels although if you'd like to reduce fin drag even further you can do it........….

Good Luck
 

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Discussion Starter #345
So been days. I have been working on other projects for quick sales. Cause that's what I do.
Anyway, worked on the flywheel today. What do you think?? First two are the cut fins, then second two are the cut fins ground down.
Should I ground down the rest a bit?? Thinking back, I believe CAM2 said trim the rest 3/8" . Easy mod for sure so far maybe 15min. Less removable time.
Next need to perfect the reed cage mod. Failed the first attempt and have 2 new ones coming.

The 3/8" finclip mod is for the pistomported fl;ywheels as theyre unlike the reeded engine flywheels although if you'd like to reduce fin drag even further you can do it........….

Good Luck
Hhhmmm, maybe this one is I'll leave. Next one will be the same as this plus 3/8" trim. Maybe another with just the tips trimmed, maybe 1/8" along with every third fin cut.
 

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It does not have to be pretty, just functional.
 

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Discussion Starter #347
It does not have to be pretty, just functional.
Well said and true. The only things seen are the pullstart, clutch cover, and outside cyl head a little along with the spark plug wire. I'll do my best for the functional part. I like sleepers.
 

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Discussion Starter #348
Well, I finally finished my first clutch. Thanks to CAM2 and EPR for all your help. Heavy Springs I have are about 1.50 and stock was 1.40 millimeters. The arms were26.7 grams, 26.9, 27.3 before. Then
25.8, 25.9, 25.9 grams. I also weighed the bolts and centerpieces, because I had extra laying around from Bad clutches. So it should be a pretty light clutch. Total weight 169.3g.
I'll keep you updated on this first engine build which will be using a CAM2 special 2 piece head. And hopefully a decent blueprinted bottom and 2nd try reed plate mod.
 

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Great work, it will be fine. I was blown away when just a few grams lighter & hp springs makes a big difference, the lighter the arms the more the springs hold back till more rpms.
 

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Discussion Starter #350 (Edited)
Great work, it will be fine. I was blown away when just a few grams lighter & hp springs makes a big difference, the lighter the arms the more the springs hold back till more rpms.
Yes, it totally makes sense. And quite amazing of how simple it really is. It really doesn't take that much work. I can't wait to try it out on all of my engines from now on. Even the ones that I flip.
 

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Dude, we all mess up from time to time, lol. What I do is cut .200" off the end of the fingers, then regrind the arc from 1/4" from the bottom inside till the fingers ends are pointed again, which lets them open more. One of my FC crank engines I ground them back to far and ends of CF reeds were riding on the crank halves, lol.

The ID of that manifold, is .565" the carb is .500" ID on that side. On the 13mm stock piston carb I leave the venturi in the middle alone, I taper the back side to .565" to match the intake ID, or you can make both even more, Then I taper bore the front of the carb to match the alum offset hole in the V-stack for this carb, I also taper the bore in front hole in the stack bigger then you match it with the hole in the front of the carb.
The first engine is a Boosted306 engine 49cc, the second one I built, both will be sold when it gets warm. Have a 47cc Boosted engine that looks just like the 49cc 306 engine. The two Boosted twin drag engines will be for sale also, they have a 4 reed block and 16mm Walbro HDA48D pumper carb with single inlet no return line, perfect for a Cag.
 

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Discussion Starter #353
You know, 44mm 10mm wrist pin are hard to find. Is the 40mm 10mm pin usable with a 44mm piston???

Where do you guys trim the head to get better squish?? Or what is that process?
Thanks.
 

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Discussion Starter #354
Dude, we all mess up from time to time, lol. What I do is cut .200" off the end of the fingers, then regrind the arc from 1/4" from the bottom inside till the fingers ends are pointed again, which lets them open more. One of my FC crank engines I ground them back to far and ends of CF reeds were riding on the crank halves, lol.

The ID of that manifold, is .565" the carb is .500" ID on that side. On the 13mm stock piston carb I leave the venturi in the middle alone, I taper the back side to .565" to match the intake ID, or you can make both even more, Then I taper bore the front of the carb to match the alum offset hole in the V-stack for this carb, I also taper the bore in front hole in the stack bigger then you match it with the hole in the front of the carb.
The first engine is a Boosted306 engine 49cc, the second one I built, both will be sold when it gets warm. Have a 47cc Boosted engine that looks just like the 49cc 306 engine. The two Boosted twin drag engines will be for sale also, they have a 4 reed block and 16mm Walbro HDA48D pumper carb with single inlet no return line, perfect for a Cag.
I do like the sound of those engines. I know 10-15yrs ago the pocket bike stuff was huge. It sorta died off. I think there is a slight comeback. We will see.
A lot of people just want to buy a running bike, usually brand new. Dont even want to buy a chassis and engine separate and bolt together. Im late to the game even though I was interested back in the late 90's.
Even mini bike no one wants to work on.
 

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You don't modify the round finned head it's all with the cyld height for squish, where the piston sits in the cyld at TDC & BDC, and port and exhaust sizes and shapes. Just like the 2 pc cyld CAM2 sent you. Have to go to my other computer to post photos tomorrow. You can see the billet reed box 4 reed system. The last photo you can see the ring on top off the black cyld. The one CAM2 sent you has a ring on top, the head fits over that head ring and has a .020" thick round copper gasket in between. You make OD of the ring/barrel just slide into the head opening. I use Permatex high temp copper head gasket spray on all gaskets, paper or copper or alum.
 

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Discussion Starter #356
Hey for the 2 Pc heads, what spark plug brand do you guys use?? I bought some cheap Chinese but I know I need to keep spares around and want some better quality. Thanks in advance.
 

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Well, the round finned head I sent you has a 10mm long thread, and the engine I sent you with the round alum alloy head has a 10mm plug also. But, the Billet Winged head uses the stock 14mm short plug. I use NGK in all my engines, 10 or 14mm.
The billet engine I am going to put a Diamond Fire 14mm plug, #E3-12, there is a ring around the plug electrode for better spark. About $6 plus. Also, looking for the right # for my X18 110cc four stroke. I bought one but its a little to long, I made a brass spacer that I think will work. Next time I will get the right one. The 14mm NGK is like BM6A, BM7A I believe. the bigger the number the colder the plug, Some plugs with an R is a resistor plug. You might search for Posts from CAM2, click on his blue name and click, see all post by CAMs, and look for info on spark plugs numbers.
 

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On a different lap top, here is an update; The long 10mm plug I use on CAG hp heads is NGK C7HSA. I always break the engine in with the China plug, then change. Here are some photos that might help you.
See the last photo, be it reed or piston port where the piston is is what you want, you have grind the top of the head to look like that and then surface the top. The head slips over the ring on the cyld and hits the round copper head gasket so it has to be very flat. The other 4 photos are of the magic that Boosted306, who is retired made I have 5 different engine with his stuff.
 

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Discussion Starter #359
On a different lap top, here is an update; The long 10mm plug I use on CAG hp heads is NGK C7HSA. I always break the engine in with the China plug, then change. Here are some photos that might help you.
See the last photo, be it reed or piston port where the piston is is what you want, you have grind the top of the head to look like that and then surface the top. The head slips over the ring on the cyld and hits the round copper head gasket so it has to be very flat. The other 4 photos are of the magic that Boosted306, who is retired made I have 5 different engine with his stuff.
Thanks, I appreciate that. Trying to get the misc stuff I know I don't have yet. Trying to finish a few projects then finish up this motor.
 

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See the cyld with one wide upper port, I take the 2 upper port cyld and Dremel out the center pc with a 3/8" barrel cutter. It's pretty easy, Then I run a no port piston. Learned that from Sam, ( Boosted306 ). On the cut cyld it don't have to be pretty, the head is going to cover it. The most important part is the top where the copper head gasket sits, the side of the barrel only has to slip into the head, I use files, sand paper, ( wet & dry is the best ) mostly, and the barrel cutter around the outside of the ring. When I was machining alum & plastics way back, I make a small surfacing block out of 1.5" Thick alum, its very flat, made it to do may drag bike stuff. I use double sided poster tape on the block and put sand paper and go to work, lol. I buy one sheet each of 100, 240, 400 and even 600 ans 1,000 grit, $1.30 a sheet. You could use a flat piece of glass.
 
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