|
wiseco
Oct 22, 2010 9:23:11 GMT -5
Post by kawonda750 on Oct 22, 2010 9:23:11 GMT -5
after the seizure of the F'nB, I got a new piston and another cylinder. I brought the cylinder to the local machine shop for boring. This guy does alot of snow machines as well as car engines and seems up on his 2 strokes. he says that people he knows don't call it wiseco but "Seizeco" The specs as per mraxl for piston clearance is .0023 to .0028 but the Wiseco box says a min of .003. He says he likes to leave more, even up to.005 because Wiseco's tend to expand more. I have seen you guys talking about as little as .0020. I would have preferred to get Wossners but I only needed 1 piston. So, what do you think? Dave
|
|
|
wiseco
Oct 22, 2010 10:54:49 GMT -5
Post by lc on Oct 22, 2010 10:54:49 GMT -5
Wiseco's have changed over the years. Yes, years ago the old trick was to run them, wait for a mild seize and sand off the high spots. This does not seem to be the case anymore.
Do you want to listen to it rattle from new? .003" is too loose. Leo runs even tighter than .002 and pushes a new set of bores hard during racing. Leo has also stated that .002 is entirely safe on an H1 (provided the jetting is not way off).
Both Walms and I are running .002 on our 500's and have not seized. I now have 5600 kms on my bores. I always let the engine come up to full temp before flogging it.
Be sure your intake manifolds are mounted and torqued on the cylinder(s) and your machinist checks the bores for taper after they cool off from final honing. The triples are known to change their dimensions as they return to room temp.
J
|
|
Deleted
Deleted Member
Posts: 0
|
wiseco
Oct 22, 2010 11:00:31 GMT -5
Post by Deleted on Oct 22, 2010 11:00:31 GMT -5
they do swell up. My B rattles like a SOB until hot. Once hot not a sound. Do em to spec and they should be fine. Many actually run em tighter than spec. LC can add to this as he is running like .oo2 no problems. The 250 KX was like .oo3 and not a knock or rattle at any temperature or RPM
|
|
|
wiseco
Oct 22, 2010 11:04:52 GMT -5
Post by lc on Oct 22, 2010 11:04:52 GMT -5
Donnie, I believe your "swelling" pistons are the early version I referred (possibly cast) with the d**es rings? Don't forget your KX has a liquid jacket to quiet things and better control temps.
J
|
|
|
wiseco
Oct 22, 2010 11:06:51 GMT -5
Post by lc on Oct 22, 2010 11:06:51 GMT -5
The cuss filter seems not to like the proper name given to the "L" shaped rings!!! LOL! J
|
|
Deleted
Deleted Member
Posts: 0
|
wiseco
Oct 22, 2010 11:22:28 GMT -5
Post by Deleted on Oct 22, 2010 11:22:28 GMT -5
thanks LC. You swear too much. ;D
|
|
|
wiseco
Oct 22, 2010 12:50:25 GMT -5
Post by Jim on Oct 22, 2010 12:50:25 GMT -5
Donnie, I believe your "swelling" pistons are the early version I referred (possibly cast) with the d**es rings? Don't forget your KX has a liquid jacket to quiet things and better control temps. J LC, I'm still running a set of old Wisecos with d**es rings, and they are forged. I look forward to trying a set of Woss**rs next time.
|
|
|
wiseco
Oct 22, 2010 12:58:05 GMT -5
Post by lc on Oct 22, 2010 12:58:05 GMT -5
Jim, I trust you are referring to an H2? Back in the mid 70's (the old wisecos I referred) the H1's pistons were noticeably heavy walled (skirt area) and cast. One could actually feel the weight difference between a wiseco and stock piston (stock being lighter).
Forged pistons from Wiseco for the H1 were not available then. However, the H2 pistons were indeed forged.
J
|
|
|
wiseco
Oct 22, 2010 13:08:00 GMT -5
Post by Jim on Oct 22, 2010 13:08:00 GMT -5
OK, I appreciate the information, LC. These pistons are H2 pistons from the '70s. I guess back then I was dealing only with H2 pistons, so I missed out on the H1 difference(s).
|
|
|
wiseco
Oct 22, 2010 14:00:15 GMT -5
Post by kawonda750 on Oct 22, 2010 14:00:15 GMT -5
Necessity dictates that I put it together as it is. It turns out that the cylinder was already 3rd over and not standard bore as the seller had thought and a hone was all the machine shop could do. It runs nicely though and sounds good. I guess I'll live with it at .003 as measured. I am sure that the seller would replace it with a standard bore if I asked him but we measured the other cylinders which I received re-bored and with new pistons when I got this bike and they are in the same range. i don't want one cylinder with .002 and rest with .003.
|
|
|
wiseco
Oct 22, 2010 14:23:34 GMT -5
Post by lc on Oct 22, 2010 14:23:34 GMT -5
It will be fine.
J
|
|
|
wiseco
Oct 23, 2010 6:31:07 GMT -5
Post by Soupdragon1957 on Oct 23, 2010 6:31:07 GMT -5
I have a set of "new" Wiseco's in my 400, had it bored to Wiseco specs. Motor is still rattle free over 4000 miles since rebore, & yes, I do thrash the $hit out of it on occasion.. Last time I checked (about 1000 miles ago) the pistons still looked new, machining marks still there, no scuffing, & no blow by past the rings. FWIW have run full synthetic since initial Dino oil premix tank full.. A lot of the H1 top end noise is due to the fins ringing, try rubber dampening blocks.. SoupD.
|
|
|
wiseco
Oct 23, 2010 7:06:55 GMT -5
Post by Rick on Oct 23, 2010 7:06:55 GMT -5
I've never had a problem with Wiseco pistons
.....until they raised their prices by 30% last year....
Rick
|
|
|
wiseco
Oct 24, 2010 19:31:02 GMT -5
Post by pipe welder on Oct 24, 2010 19:31:02 GMT -5
I installed the second set of Wiseco's this year in the H2. Both were bored to .0025 not wiesco .003 recommended clearance. I did a careful break in with several heat cycles a first start up.
My engine guy also did not recommend going under .003 clearance and he warned me big time but all the guys here that have gone a 1/2 thou tight seem to have quiet reliable engines.
The only complaint I have is that out of the 6 new pistons we measured there was a .0005 to 001 difference on piston size. Both sets had one piston that had to be matched to the hole.
Thats not a big problem unless you have a seizure and your new piston is smaller than the one that seized.
Also: Rick is right. the price has gone way too high. Not sure if I would buy wiescos next time at nearly $200 a hole.
|
|
|
wiseco
Jul 7, 2014 14:12:58 GMT -5
Post by pipe welder on Jul 7, 2014 14:12:58 GMT -5
.
|
|