Husaberg Forum

Husaberg Forum (http://husaberg.org/husaberg-forums.php)
-   Mechanical (http://husaberg.org/mechanical/)
-   -   Definative main bearing thread (http://husaberg.org/mechanical/17170-definative-main-bearing-thread.html)

berglsmerg January 29th, 2014 09:16 PM

Re: Definative main bearing thread
 
The factory spec is 0.25mm to 0.35mm or 0.0098" to 0.0138". I have set up the 0.0098" clearance and erroneously referred to it as 0.9 mm in my above post, so even tighter again.

The cast piston question was my attempt at humour.... I see that work really well.

I'll measure my rod rod for you again :oops:

bushmechanic January 29th, 2014 09:26 PM

Re: Definative main bearing thread
 
ha sorry no humour today, i have 3D design crap and FE simulations running a muck on 2 computers .. my head is full of matrices and constraints that won't spin around according to their own rules in e space :oops:

if the rod still comes up short I recommend using a fluffer :D

plumbbob January 30th, 2014 12:57 AM

Re: Definative main bearing thread
 
Thanks Bushie,

it's already spread over the garage so i'll check start looking for other causes.

Could counterbalancer bearing harmonics show up as vibes? Only ask as i fitted a new pair, tight on the crank but only a push fit in the balancer...........saw the loctite tip too late!

Carl

bushmechanic January 30th, 2014 01:08 AM

Re: Definative main bearing thread
 
sure it could but I don't know much about the idiosyncrasy's of the counterbalancer, I removed mine early on and loved the change with a 75% Balance factor, now I run 58% and its better again .. 62.5% is supposed to be the sweet spot.

mine had more vibes through the pegs below 3000 but much much smoother above 4000 rpm

with your 82mm crank it might be the CB doing a funky dance, weed and others noted removing the CB without re balancing the 82mm crank though is not a good idea

tourist January 30th, 2014 01:46 AM

Re: Definative main bearing thread
 
Quote:

Originally Posted by bushmechanic
sure it could but I don't know much about the idiosyncrasy's of the counterbalancer, I removed mine early on and loved the change with a 75% Balance factor, now I run 58% and its better again .. 62.5% is supposed to be the sweet spot.

Is the 62.5% figure applicable to all the engine types? I.e. the 550 also?

bushmechanic January 30th, 2014 02:19 AM

Re: Definative main bearing thread
 
I would say yes but Ive not tested it personally

all the RFS builders are at about 62% on all their different builds and the RMZ450 which does not run a Counterbalancer is at 62%

since the majority of rmz owners don't even notice it has no balancer you have to assume its a pretty good place to start :)

ORANGEBERG January 30th, 2014 05:22 AM

Re: Definative main bearing thread
 
Interesting tech stuff Bushie, i stumbled across the right NTN bearing years ago and worked out it was good because it eliminated the problem and my warranty issues. Never studied enough to see the extra taper on the roller of an NTN, Not enough crank end float was the main problem and we had bulletins sent to us back in 2002 to open it up to at least .50mm on the KTM RFS motors. In 2005 we had to check every Husaberg bike as some had Zero from the factory I had to strip a couple and fix before i sold them. (Austrians on the piss again). Ive Been quiet lately but still get the odd rebuild sent to me.
My Husaberg weephole kit still sells around the world and if every Husaberg owner has there own CNC lathe at home in there shed im happy to share the specifications, if you dont have a lathe you just buy it off me.
Dont want be seen as making money from the site.
John ORANGEBERG

ORANGEBERG January 30th, 2014 05:44 AM

Re: Definative main bearing thread
 
My old thread on the main bearings was done in about 2007 but we had trouble in 2005 back then i was silenced by the powers above (KTM HUSABERG AUST) it went on to be one of the biggest ever on the UHE, it did get a bit off the track towards the end and we had no proof what was going on inside the engine, we were blaming oils, bad fuel, the position of the sun and moon etc but this latest post by you is very informative.
Im rebuilding my 07 650 which had NTN put in immediately off the floor and its done 10.000 hard KMs without a problem i just feel sorry for it so its getting a birthday and i have a few long distance rides coming up.
Like you said the 550 was by far the worst an the 450 occasionally, the 650 with the forged crank didnt have such a big problem.
My biggest problem lately is the primary drive nut coming loose and destroying the crank keyway and splitting the gear, must have been another Austrian factory worker who engaged in way to much AM drinking and didnt torque them up.
John ORANGEBERG

bushmechanic January 30th, 2014 08:08 PM

Re: Definative main bearing thread
 
Hey John

that's crazy stuff from them sending out bikes with no crank end float

one thing Ive not mentioned yet is that sometimes the bearing outers move inside the cases when the cases are hot and settle at zero end float as the bike cools down

then the next time you start the bike you have zero end float until the cases get at least as hot as they were when the bearing moved.

happened to my bike once.. at around 80 hrs I think .... i thought it was going to be stuffed for sure ... could not get the bearing to move back until it bike was really hot.. took 30 min easy riding before the bearing moved again and I got the end float back by tapping the end of the crank with a mallet.

so if you rev a "warm" engine that happens to have settled with zero end float....

bushmechanic February 1st, 2014 08:20 PM

reduction in axial play after rebuild
 
its probably worth mentioning that after a new build with a new crank or big end rebuild the axial play often reduces by about 0.1mm

so if you had 0.5mm on a new 650 build it will most likely end up a bit less say 0.4mm


All times are GMT -8. The time now is 03:33 PM.

Copyright © 2021 Husaberg Forum. All rights reserved.