Re: Vrod is getting a refresh



Snag wrote:

Roger M wrote:
Taxmanhog wrote:

"Greg O" <goo1959SPAM@xxxxxxxxxxx> wrote in message
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"Taxmanhog" <taxmanhog@xxxxxxxxxxx> wrote in message
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Shirley

Round for the house & Top shelf for Roger M & Roger TCW.

Little more time analyzing the current situation before I jump
headlong into the rebuild.

I measured the front & rear cylinders & Pistons at several
locations to search for possible irregularities. The Ideal numbers
are 4.250" bore &
4.247" piston which would be worn to max tolerance of .003 for
running interference.


Are you saying the piston to cylinder is an interference fit when
cold? I remember rebuilding a Mitsubishi four cylinder that had
piston to wall clearance of something like 1/2 thousands of a inch.
I remember after boring the cylinders and fitting the pistons you
could slip a piston it the bore, and it would not slide down, you
had to give it a slight push to move it. It made me a bit nervous,
rebuilding that thing. I remember questioning the piston/cylinder
specs, but an engine builder told me it was normal. Oiled the bores
and pistons well on assembly, and no problems! The car belonged to
a friend of mine and he ran it for quite a few years after that.

.0005 that's a tight fit!

Yes, the HD service manual say's .003 or more and it's time look at
replacement of the piston & sleeve.

I got further clarification today, that this is measured at the
skirt area near the bottom & and up 10mm from that point.

I have a lot of slap 10 thou on the front & 18 thou on the rear

Wiseco & the shop that did the big bore are not standing behind
their work & materials. time to move on......



A few things. 5 tenths is not unheard of in car engines. The
machining has to be spot on but it's not uncommon. Using factory
specs on what is essentially a race engine is just asking for
trouble. Measuring tore up parts from a broken engine is a waste of
time, it's meaningless to measure the pistons. Measuring the sleeves
only matters if you're planning on going oversize with them. Wiseco
makes top shelf parts and their machining is as good. I've used their
parts and services on many occasions and have never had a problem. As
far as the shop that put the engine together goes, who knows. I
suspect they built that bike and then beat the *** out of it on a
dyno trying the get the best numbers they could. You bought a bike
with a built racing engine on it, expecting anyone to warranty or
guarantee it is asking a bit much in my opinion unless you only had
it for a few days.

Personally on every engine I build I like to heat cycle them a couple
of times before any usage of them. Most people don't have a clue
about heat cycling and think it does something to the metals inside
of the engine. Not so, actually all it does is let everything expand
fully at full operating temperature and then contract back when cold.
It lets thing find their place sort of. You can put things together
perfectly but until all the housing bores and parts expand and
contract they aren't where they want to be. I don't have problems
with engines that I build and I think it's mostly because I'm
thorough in the way I do things. That includes not beatin' on a fresh
engine no matter what I built it for.



Roger
but here i'm nobody
^^^^^^^^^^^^^^^^^^^^^^^^
Thass bull*** . Your opinion is respected here by some of us . When I
built the motor in the shovel , The KB piston instructions said I could run
them as tight as .00075 . So that's the number I shot for . I believe in
building them tight and runnin' them in easy . Let those parts hone
themselves into a closer running fit and it's going to last longer . Be anal
about the numbers !
After I see what my annual bonus is , I'll have an idea what I can afford
to do this winter ... tranny is coming apart for a checkup no matter what
though . Along with the new swingarm bushings (V2) sitting in front of me .
Gonna have me one TightAssBagger when I get done !
--


Thanks, but of all people I would think you'd hate me. I guess some people
relaize I can't help who I am.



Roger
at times that'd be I'm
Asswipe, me

.

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