Finished building the engine for my AF project

Post by **AlisoBob** » January 11th, 2011, 4:41 pm

blownbillybob wrote:Cyl. finish looks a little rough....

A little?

Roostys work

south central hoon · January 11th, 2011, 5:31 pm

I know I'm opening a can of worms here, so be it.

Adam's cylinder finish is pretty and I'm sure it works great, but is (from the photo provided) the cross hatch deep enough to hold premix to lube the cylinder? Will it actually work any better than the cylinder with the rougher finish?

i guess what i'm saying is deep cross hatch = more lubrication (to a point obviously), right?

interested to hear opinions on this...

oh, been meaning to ask a question for Roosty....

what clearances do you set up new cylinders with on a cast piston? skirt clearance? ring gap?

just curious.....

thanks

blownbillybob · Post by **blownbillybob** » January 11th, 2011, 9:19 pm

To rough of a finish will leave a superficial crosshatch which will scrub off rightaway leaving a rough bored surface to ride on and cause premature wear and on a four stroke oil consumption

A good hone surface will distribute oil,hold oil and have enough flat area so the piston can ride on the cyl wall with out touching kinda like a bearing on a four stroke

The crs have a chrome ring face but a thin ring package which with to rough of a finish will premature ly wear them out you want your finish to resemble a broke in cyl but still be able to seat the rings

Hope that helps alittle and I'm sure I forgot something??????

Post by **AlisoBob** » January 11th, 2011, 10:41 pm

Look at the EG bore. The same finish of the cylinder is visable in the decomp scallops.... Ball hone job give-a-way.

Look at Roostys.... Scallops are untouched. Only possible when hard stones are used.

Roostys cylinder is round, straight, and as smooth as a baby's bottom.

No " Break-In" required and the rings will last at least 2x as long.

Its quality work.

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » January 12th, 2011, 5:57 am

I have a new honda cylinder here, theyre very fine.

Cast pistons i like to go .0035, .003 at the tightest, rings are coming out of the box at .016" usually, thats good. they can be anywhere up to .020 and not make a difference.
The wiseco ring from every piston but the new coated one we setup at .018"
the wiseco had been looking for .003" on all the non coated pistons, we'd go .004 forsure, the new coated one says .0025, becasue .0005 is involving the coating, we'd like to keep these at their spec.

I've run cast pistons up to .0055

I've run a vertex at .0025, I have a prox in the bridgeless engine at .003

blownbillybob · Post by **blownbillybob** » January 12th, 2011, 7:30 am

I run noncoated wiesco at .0037
I just did a pro-x at .0025 on my own bike
Had another pro-x on a last second freshen up before a ride at .0055 once the rings broke in it kicked over like a 125 and sounded like a schermin tank lol,,,,, but still ran good!!!!!

blownbillybob · Post by **blownbillybob** » January 12th, 2011, 1:04 pm

Dogger wrote on ATM

Projected spark plug used to raise comp.

I thought they were used to get the spark further in the mix????

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » January 12th, 2011, 1:36 pm

ya, idea is that the mixture is deflecting off the dome before it reaches the plug.

robfromga · Post by **robfromga** » January 12th, 2011, 3:49 pm

What ia the plug #?

dogger315 · Post by **dogger315** » January 12th, 2011, 7:39 pm

Dogger wrote on ATM
Projected spark plug used to raise comp.

What I actually said was:
The base of the cylinder head was also machined and a projected
nose spark plug is used to raise compression.

I should have posted the build series here first so you guys could
catch all the editorial mistakes I made - Looks like you're already
well on your way to accomplishing that.

It should read as: The base of the cylinder head was machined to
raise the compression and a projected nose spark plug is used.

I will make the appropriate correction on the ATM post.

What ia the plug #?

NGK BP8EV

dogger

robfromga · Post by **robfromga** » January 12th, 2011, 8:04 pm

dogger315 wrote:
Dogger wrote on ATM
Projected spark plug used to raise comp.
What I actually said was:
The base of the cylinder head was also machined and a projected
nose spark plug is used to raise compression.

I should have posted the build series here first so you guys could
catch all the editorial mistakes I made - Looks like you're already
well on your way to accomplishing that.

It should read as: The base of the cylinder head was machined to
raise the compression and a projected nose spark plug is used.

I will make the appropriate correction on the ATM post.

What ia the plug #?
NGK BP8EV

dogger

sorry to totally jack the thread.....is there any benefit in a stock motor to the projected nose plug?

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » January 13th, 2011, 5:44 am

Roostius_Maximus wrote:ya, idea is that the mixture is deflecting off the dome before it reaches the plug.

robfromga · Post by **robfromga** » January 13th, 2011, 6:11 am

Roostius_Maximus wrote:
Roostius_Maximus wrote:ya, idea is that the mixture is deflecting off the dome before it reaches the plug.

So what does it mean for a foo like me? Do it give a nutter powa band? Ehh?

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » January 13th, 2011, 6:25 am

it means that gorr figures the fuel is deflecting off the head and away from where the plug is located stock, so he uses a longer plug to reach to where he figures its working best

robfromga · Post by **robfromga** » January 13th, 2011, 6:35 am

Roostius_Maximus wrote:it means that gorr figures the fuel is deflecting off the head and away from where the plug is located stock, so he uses a longer plug to reach to where he figures its working best

Ahh, hows the butt dyno work? Does it even show any improvement? Im a total newb when in comes to the 2stroke combustion chamber, but it seems like there would be a ton of other variables.

Hey...check your pm's

KE 336 · Post by **KE 336** » January 13th, 2011, 7:55 am

My only experience with EG work has been with a 250 yamaha and getting the 265 bore and mo better port. He does recommend the BP plug in most of his 2 strokes it seems. As for being able to tell a power difference from riding the bike with a BP or standard plug I felt zero change. Maybe I'm a so called nit picker like Bob but I did have a couple of quality issues with the cyl. and head I got back from EG but it was minor enough to take care myself but enough to where if I was to send something else out for work I would shop else where.
That being said, the bike did haul ass and was noticably stronger than a stock 250.

BannedCR500Riders.com

Finished building the engine for my AF project