|
Zombie
Dec 6, 2009 14:42:51 GMT -5
Post by lc on Dec 6, 2009 14:42:51 GMT -5
Redline? Is that where the engine finally stops pulling?? Givr, I guess your decision all boils down to "acceptable risk" VS $$ outlay before and AFTER possible destruction! To quote Inspector Harry Calahan of the SFDP: "Do you feel lucky PUNK.....well do ya? J
|
|
|
Zombie
Dec 6, 2009 17:43:29 GMT -5
Post by Soupdragon1957 on Dec 6, 2009 17:43:29 GMT -5
Redline? Is that where the engine finally stops pulling?? J Nope, that's where my mechanical sympathy kicks in.. SoupD.
|
|
|
Zombie
Dec 6, 2009 19:08:12 GMT -5
Post by givr on Dec 6, 2009 19:08:12 GMT -5
Thanks for the banter guys. Plan B is to use the acceptable H2B cyl's and pistons I have. But it is a long winter....
|
|
|
Zombie
Dec 7, 2009 8:13:46 GMT -5
Post by givr on Dec 7, 2009 8:13:46 GMT -5
Sometimes I feel sheepish seeing the "triples master" status, just because I've posted a bunch of times. Let's just say, "hyper triple enthusiast". Having said that, I measured a couple of the bores near the top of the cylinder and the near the bottom. I found that the .040 over barrels actually measure 71.75mm at the top. I would have thought they'd be slightly larger than 72mm as .040" is slightly larger than 1mm and the standard bores were 71mm. So what gives? I'm going to buy pistons, but am now uncertain as to what size to buy. Do I get 72mm (2nd over) or 72.5mm (3rd over) ? Don't want to have to get more material bored out if I don't need to. Sincerely, Top end rookie.
|
|
|
Zombie
Dec 7, 2009 12:07:23 GMT -5
Post by JA-Moo on Dec 7, 2009 12:07:23 GMT -5
Properly bored cylinders are "fit" to the pistons, not to a standard measurment.
Do you have the pistons? Do a comparison measurment to see what over size you need to go.
|
|
|
Zombie
Dec 7, 2009 12:22:32 GMT -5
Post by lc on Dec 7, 2009 12:22:32 GMT -5
Good question. The trouble is current oversize pistons from Wiseco etc. may be a different size from 35 years back.
For example: The bores of my "Looneys" are in excellent shape with most cross hatch still showing. As such I purchased a current set of first over Wisecos figuring all I had to do was run a ball hone through the bores. Upon measuring the bores and the new pistons I found the clearance to be .006in. DRAT!
The point being is stated oversize is a generic term. A bore must be machined to the specific piston. To answer your question the actual proposed piston to be used would have to be measured before you could determine whether you could re use your present bore. Don't forget you may also need a couple of thou for a fixed hone to straighten your used bores.
Also, the bores wear in several spots that must be measured typically just above the exhaust port, a CM below the top, and just below the intake port.
So, If your proposed piston measures 72mm and your bores have no gouges you may be able to do it. Knowing the exact dimension at the piston skirt is the key.
J
|
|
Deleted
Deleted Member
Posts: 0
|
Zombie
Dec 7, 2009 14:05:57 GMT -5
Post by Deleted on Dec 7, 2009 14:05:57 GMT -5
Dan Douglas over in Brantford is real good. He is one heck of an engine builder too. Him and his dad have been boring cylinders for decades, H1 and H2's as well. Soup seen the bang-up job he has done for me in the past and his cylinders fit the pistons like a condom. The chamfering on the ports was done so nice too. This is an area some of us need to stay clear of and let a pro do his thing, me included. Cylinders don't wear in a perfect circle either, the bores get all oblong. Better off with a fresh start and a nice fit
|
|
|
Zombie
Dec 7, 2009 14:30:49 GMT -5
Post by H2 Dude on Dec 7, 2009 14:30:49 GMT -5
better off with a fresh start and a nice fit
That's what I did with the H1B project .
|
|
|
Zombie
Dec 7, 2009 14:41:34 GMT -5
Post by givr on Dec 7, 2009 14:41:34 GMT -5
Better off with a fresh start and a nice fit Does that apply to wives too? ;D Glad she doesn't check here.
|
|
|
Zombie
Dec 7, 2009 14:46:23 GMT -5
Post by H2 Dude on Dec 7, 2009 14:46:23 GMT -5
Hahaha we would ALL be in trouble..lmao
|
|
|
Zombie
Dec 13, 2009 15:19:42 GMT -5
Post by givr on Dec 13, 2009 15:19:42 GMT -5
OK, new pistons ordered, so I gotta get some pipes happenin'. Bead blasting the cyl's right now. Got some misc parts dropped at my house by some tripler. ;D Getting some ideas for a chop job a la Drewski. Really like that 72 tail section.
|
|
|
Zombie
Dec 13, 2009 15:28:14 GMT -5
Post by tripletwerp on Dec 13, 2009 15:28:14 GMT -5
OK, new pistons ordered, so I gotta get some pipes happenin'. Bead blasting the cyl's right now. Got some misc parts dropped at my house by some tripler. ;D Getting some ideas for a chop job a la Drewski. Really like that 72 tail section. If you don't know what is factory correct you will never know that your decal is wrong. Educate yourself and do some research to what is correct and you will be respraying the bike and using RB's decal....and sleeping at night again. ;D
|
|
|
Zombie
Dec 13, 2009 15:34:55 GMT -5
Post by givr on Dec 13, 2009 15:34:55 GMT -5
I won't be sleeping until everything's NOS. ;D
|
|
|
Zombie
Dec 13, 2009 15:49:45 GMT -5
Post by tripletwerp on Dec 13, 2009 15:49:45 GMT -5
|
|
|
Zombie
Dec 13, 2009 17:06:51 GMT -5
Post by H2 Dude on Dec 13, 2009 17:06:51 GMT -5
If you don't know what is factory correct you will never know that your decal is wrong. Educate yourself and do some research to what is correct and you will be respraying the bike and using RB's decal....and sleeping at night again.hahaha Now where Did I read this..HMMM
|
|