Who's making fun of BB kits! Mahle just joined the club!!!

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blsnelling
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I know the OP said he's going to modd it but, I still think I would want a new one, I don't think I would have much faith in running that saw knowing what the jug looked like.

That entire area gets modified when I work on a 7900. Unless there's more serious flaws with it, it's not really worth sending back. How do the ports look?
 
atlarge54

atlarge54

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Looks like that would be a good candidate for some precision measurements to be taken. Hope the machining department did a better job than the casting department.
 
barney34

barney34

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7900 cylinder

That entire area gets modified when I work on a 7900. Unless there's more serious flaws with it, it's not really worth sending back. How do the ports look?

ive never seen a casting look like that on any 7900 ive ever seen. i wouldnt think twice about sending it back. ie always been very impressed with the quality and consistency of the 7900. you should get what you pay for
 
CHEVYTOWN13

CHEVYTOWN13

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You expect more from the best

All you hometowns are making valid points.

Al, the piston is what was a bummer. Someone who doesn't port would just slap that on. Those edges are not as strong as a straight cut. That will bring more stability I would assume. Ronny, Mahle kicks azz bro; not sure what happened here.

The ports and beveling look nirvana. A thing of art fo show. And yes, I can see from this shot that that's the way the ports are. But dang, it just doesn't look like it's cool for school man.

DSCF1522.jpg


And it will run no doubt. But will it run at it's optimum? Probably not. The air flowing around that looks like BAD flow to me. Too much flash for my taste too.

I couldn't find any pieces of the piston skirt in the box. And the back looks like a great casting. So that was a shocker compared to the 5100/510/6401's slugs.

Since I'm going to be porting it, I see no reason to send it back. If it was a stocker, shoot, I'd be going back for a new pair of shoes.

Using the Mex Port, I'll be taking off the left side and making it square to the north east corner in the picture. The bottom will get a routered straight edge too. The port will look square hopefully. I'm holding the cylinder with a finger through the exhaust port right abouts where it would be when the transfers are opened.

DSCF1517.jpg


For quality, I've seen better on the other Mahle cylinder's I've played with. The 5100 had similar castings to this cylinder. So some work is in order.

Here is the Husq 365

DSCF1520.jpg


I was hoping for some finger ports, but DAMN:jawdrop:, the cylinder is thin in that area!

DSCF1519.jpg
 
tdi-rick

tdi-rick

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And here's my 7900 cylinder and piston to compare.

Unfortunately I'd already got to the piston before the pics we taken so you'll all have to take my word it wasn't as bad as Ricks, but I re-bevelled it anyway. The chamfer helps retain oil on the cylinder wall rather than the skirt scraping it away.

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tdi-rick

tdi-rick

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[snip]

The ports and beveling look nirvana. A thing of art fo show. And yes, I can see from this shot that that's the way the ports are. But dang, it just doesn't look like it's cool for school man.

[snip]

My jug has a tiny lip in the inlet and exhaust ports just before the cylinder wall right where you don't want it.
They'll go when I clean the casting up, and I'm tempted to just clean the castings and put it back together for some timed cuts just to see how much gain there is in just removing the casting flash, then pull it down and do it for real, if I make the time :D
 
AUSSIE1

AUSSIE1

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My jug has a tiny lip in the inlet and exhaust ports just before the cylinder wall right where you don't want it.
They'll go when I clean the casting up, and I'm tempted to just clean the castings and put it back together for some timed cuts just to see how much gain there is in just removing the casting flash, then pull it down and do it for real, if I make the time :D

Make the time! :) :popcorn:
 
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