Weekend at the workbench

GreasyChris

Well-Known Member
Local time
7:05 AM
Joined
Jan 3, 2019
Messages
1,666
Location
London, Ontario
So I had installed a set of Topgun suspension forks on my bike and let me tell you they are junk. As I am waiting for new forks to arrive I decided that since I have about 20hrs runtime on my engine i would take the engine apart and see how things are and do some upgrades i didn't do when i put the bike together.

This is what i did this weekend. Open up and cleaned up transfer ports and direct flow towards intake.
Flow test the transfer ports with water to see how the transfers charge towards the intake.
Clean up exhaust port and widen
Portmatch case and jug. ( was previously done, but did some more)
Added boost port to intake side of jug.

Lightened piston, removed material from the inside.
Notched piston skirt on intake side.( previously done but I'm using a new piston so I did it again.
Ramped piston towards transfer ports and exhaust port. (Previously done as well)
Better balanced crank
Stuffed crankcase.

Once the jb weld cures in the crank I will set the squish gap with a stock piston then replace with my ramped piston.

Also order a new expansion chamber. And installing a Reed valve
Hopefully forks and new pipe will be here soon so I can get this all back together.

Someone has to keep up to Spare parts. Lol

Thanks to @spareparts @gary55 @streetryderz for all their help and wealth of information

Pics to follow

20190602_162120.jpg
20190602_162100.jpg
20190602_162041.jpg
20190602_162011.jpg
20190602_162003.jpg
20190602_161855.jpg
20190602_161853.jpg
20190602_161824.jpg
20190602_161750.jpg
20190602_161734.jpg
20190602_161648.jpg
20190602_161616.jpg
20190601_085154.jpg

s-l400.jpg
 
Well this will sound dumb, but I'll stay dumb if I don't ask. What are the 1/4 things in the case? Looks like it's gonna get with it. One thing ramping the piston on all ports will help the flow if the piston is not fully uncovering the ports, but the blowdown time will remain the same.
 
Last edited:
Well this will sound dumb, but I'll stay dumb if I don't ask. What are the 1/4 things in the case? Looks like it's gonna get with it. One thing ramping the piston on all ports will help the flow if the piston is not fully uncovering the ports, but the blowdown time will remain the same.
Hi Gary, those are stick on wheel weights, they are nice and thin. I was checking to see if they would fit in the case to help take up case volume. They just clear the crank. Im gonna buzz them down a little bit just to be sure and stick them on with some jb weld.

I ramped the piston just to the ports, they weren't quite uncovered at BDC, put a small channel in the top of the piston to help direct the charge towards the intake. Pistons are cheap and I like trying different things. I have about 4mm blowdown right now. Hopefully tomorrow night I start the reassembly and get the degree wheel on it and see what's what. I didn't really have any complaints before I took it all apart but if you can get more jam from the jar why not? Lol. I really appreciate your feedback gary
 
Why are you working on it in your kids room? Lol!

Looks like you were having some fun with it. Clean work, the case matching looks real good. Good time to match the gasket and make some spares.
 
Why are you working on it in your kids room? Lol!

Looks like you were having some fun with it. Clean work, the case matching looks real good. Good time to match the gasket and make some spares.
Lol that's my man cave in the basement where I do all my tinkering. The wife gets the main floor, I get the basement and back yard lol.
Thanks for the compliments. 😀

Oh yeah I'll be making spare base gaskets before it goes back together that's for sure. Im hoping the expansion pipe doesn't require to much modifying to get on. Im sure I'll be picking your brain once it comes in.
 
Hi Gary, those are stick on wheel weights, they are nice and thin. I was checking to see if they would fit in the case to help take up case volume. They just clear the crank. Im gonna buzz them down a little bit just to be sure and stick them on with some jb weld.

I ramped the piston just to the ports, they weren't quite uncovered at BDC, put a small channel in the top of the piston to help direct the charge towards the intake. Pistons are cheap and I like trying different things. I have about 4mm blowdown right now. Hopefully tomorrow night I start the reassembly and get the degree wheel on it and see what's what. I didn't really have any complaints before I took it all apart but if you can get more jam from the jar why not? Lol. I really appreciate your feedback gary
Love what your doing. It's your bike and your definitely not afraid to work on it, but I am real skeptical about those weights in the case holding up to the vibration. Hope I'm wrong.
 
Love what your doing. It's your bike and your definitely not afraid to work on it, but I am real skeptical about those weights in the case holding up to the vibration. Hope I'm wrong.
I've read about guys using jb weld to fill the case around the bearing journal. I was just trying to come up with other methods. I hope it works but there's only one way to find out. Testing and tuning on these is much more affordable than on a hemi challenger especially when things go bad lol. Worst case scenario is im out a $100 or so. I really enjoy tinkering with these little engines. I can sit at my work bench and do everything easily. Whereas fixing cars at work for the public isnt that much fun at all especially after 25 years. Nothing is easy to get at or fun to work on and the stuff that is fun to work on is expensive. I really like the affordability of this hobby that's for sure. I've already got ideas for other bikes id like to build. A trike sounds like a really cool build. I'm hoping the wheel weight idea works but if it doesn't I won't be ashamed to let everyone know.
 
For curiosity the wheel weights measure 15mm x 20mm x 2.8mm
They just clear now. Im going to shave them down to 2.5mm
I will update on the results
 
I've read about guys using jb weld to fill the case around the bearing journal. I was just trying to come up with other methods. I hope it works but there's only one way to find out. Testing and tuning on these is much more affordable than on a hemi challenger especially when things go bad lol. Worst case scenario is im out a $100 or so. I really enjoy tinkering with these little engines. I can sit at my work bench and do everything easily. Whereas fixing cars at work for the public isnt that much fun at all especially after 25 years. Nothing is easy to get at or fun to work on and the stuff that is fun to work on is expensive. I really like the affordability of this hobby that's for sure. I've already got ideas for other bikes id like to build. A trike sounds like a really cool build. I'm hoping the wheel weight idea works but if it doesn't I won't be ashamed to let everyone know.
I hope it works too Bro cause ti would be a sweet way to stuff these things. I agree these things are a cheap way to get your mad scientist on. You probably couldn't buy a good set of rings for your Hemi for the price of 1 of these kits.
 
Back
Top