Porting a 5000 Plus

[stinkbait]

I'm porting this saw for Igpoe. It ran good before I got it, but he wants more from it. This saw will be a toy for him.

The saw was pretty nasty.

Cleaned up and degree wheel on.

All the crap that I scraped off.

The stock #s

in - 146
ex - 75
trans - 120
bd - 15

Target #s

in - 155
ex - 80
trans - 126
bd - 17

Any input on my target #s would be greatly appreciated.

 

[ford832]

Sorry,can't help on your numbers but I can rep you for having the wisdom to work on a 5000.Now don't blow it up:msp_wink:

 

[SawTroll]

I'm porting this saw for Igpoe. It ran good before I got it, but he wants more from it. This saw will be a toy for him.

.....

The stock #s

in - 146
ex - 75
trans - 120
bd - 15

Target #s

in - 155
ex - 80
trans - 126
bd - 17

Any input on my target #s would be greatly appreciated.

I understand the intake (the whole system) is a weak point in the design of those saws, and of course the small carb. Are you doing anything with that?

 

[thomas1]

I didn't think Dean owned any saws without helper handles?

Good luck with the build.

 

[barneyrb]

If you are not cutting the squish band or making a pop-up I'm thinking raising the exhaust that much will lower compression more than desired.....I may be wrong but that is my line of thinking......

 

[rbmopar]

Do you have your intake and exhaust numbers switched around?

 

[stinkbait]

I understand the intake (the whole system) is a weak point in the design of those saws, and of course the small carb. Are you doing anything with that?

I would like to, but I don't have any carbs laying around that has the correct linkage. The whole choke/air filter setup is really restrictive.

If you are not cutting the squish band or making a pop-up I'm thinking raising the exhaust that much will lower compression more than desired.....I may be wrong but that is my line of thinking......

I'm removing the gasket and a little from the base as well.

Do you have your intake and exhaust numbers switched around?

See if these numbers are to your liking

Stock #s

in - 73
ex - 105
trans - 120
bd - 15

Target #s

in - 77.5
ex - 100
trans - 126
bd - 17

The only thing that worrys me is adding 3* the transfers. Should I leave those 120 and the blowdown at 20? Or leave them at 120 and save some on the exhaust to lower the blowdown?

 

[rbmopar]

Yep! Your stock numbers look right now. I'm used to looking at things in durations so your stock numbers would be:

Ex: 150
Int: 146
Tr: 120
Blow: 15

Something is a little wonky with your projected transfer timing if it is 126 ATDC. Your target durations would be:

Ex: 160
Int: 155
Tr: 108
Blow: 26

Feel free to correct me, but thats what I figured.

 

[Jeff Lary]

Just wishing you good luck,.. I have some 5000's and am watching eagerly.

 

[RedneckChainsawRepair]

45 seconds into this video you will see a woods ported 5000 running stock small OEM carb being run by Al Smith. Strongest 0-50cc saw torque wise I think I ever run and using 3/8 chain. Watch the saw in the cut, not how long it took it took him to get to the cant. :msp_unsure:
Me in green shirt had my race ported 5000 with 272 carb on it.

[video=youtube_share;odzfIgCTceo]http://youtu.be/odzfIgCTceo[/video]

 

[stinkbait]

Yep! Your stock numbers look right now. I'm used to looking at things in durations so your stock numbers would be:

Ex: 150
Int: 146
Tr: 120
Blow: 15

Something is a little wonky with your projected transfer timing if it is 126 ATDC. Your target durations would be:

Ex: 160
Int: 155
Tr: 108
Blow: 26

Feel free to correct me, but thats what I figured.

I am all messed up now. I will look at the numbers again when I get home. I need to look at my notes.
.

 

[stinkbait]

Stock #s

in - 73
ex - 105
trans - 120
bd - 15

Target #s

in - 77.5
ex - 100
trans - 117
bd - 17

This is what it should have been.

 

[RedneckChainsawRepair]

Did you happen to check the psi on that stock 5000 by any chance?

 

[GBD]

This is what it should have been.

The "stock" durations are long for a 50cc, and the transfer is extreme. Are you sure that these are the correct ones?

 

[DSS]

I understand the intake (the whole system) is a weak point in the design of those saws, and of course the small carb. Are you doing anything with that?

The intake might be restrictive Niko, but there is nothing weak about those saws. Strongest stock 50cc saw probably ever made, IMO.

 

[DSS]

I'm interested in seeing if it's open or closed port, windowed or solid piston, I've seen all types of mix and match inside these saws.

 

[stinkbait]

Compression is 150psi. Ring gap measured .023, which is pretty large. The cylinder is closed port and the piston is windowed. The stock base gasket is .010. I plan on taking right at .020 of the base of the cylinder to get the squish where I want it. This weekend is busy for me so I hope to get a lot done on it the first of next week.

 

[jockeydeuce]

opcorn:

I swear there are none of these saws in my end of the world.....I have yet to find even a broken piece of one of them.

I am really diggin' 50cc saws lately and I NEED one of these!!...lol:msp_wub:

 

[rbmopar]

That looks better. The first time you just listed your target transfer timing as 126 duration instead of 117 ATDC, witch is the same difference.

 

[DSS]

opcorn:

I swear there are none of these saws in my end of the world.....I have yet to find even a broken piece of one of them.

I am really diggin' 50cc saws lately and I NEED one of these!!...lol:msp_wub:

I got a line on another one Rob, if it turns out to be any good I'll send it to you. I have a few now and a couple of projects. I'll let you know.