JBS 700 Kit on welded 80mm Crank

Husaberg

Help Support Husaberg:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
so there are 2 main issues people have had with these kits

headgaskets and liner to crankcase sealing

headgasket is easy once you understand how they work.

this is what I did

bushmechanic said:
For whatever it may be worth the method I use for head gaskets on my 105mm bore is extremely effective, i recently found out it is the exact same method used in top fuel Harley drag bikes.

they bore out a fiber gasket to take a copper fire ring and use a wire ring in the top of the liner to embed into the copper ring.

file.php


9348661687_4f04ab4d4b_b.jpg


it works because the fiber portion can compress a lot more than copper. the bolts can pull the head down closer to the liner out near the bolts while the copper fire ring gets maximum crush with the wire ring and in turn is strong enough to withstand the combustion forces.

the problem with the JBS (gaskets to go) fiber gaskets and their MLS gasket is that after about 9 hours the rolled steel fire ring gets fatigue cracks in it

file.php


the problem with the copper gaskets in the 105mm bore is that the head cannot be pulled down around the bolts far enough to get the required crush at the bore. It can work fine though on a 100mm bore and has been done already.. you can buy copper head gaskets for husabergs off eBay.
Click to expand...


FWIW apparently JBS have been using the oem Head gasket 8O

another solution for a high HP engine

bushmechanic said:
from FD racing.. no headgasket...

bottom line is that if you have enough crush at the bore on the fire ring nothing is going to get out

fdracing said:
at the end of the day i decide to do the metal-ring myself , it's an square ring with 2 teeth on both side i made it on stainless steel 431 , oil pressure has it's own o-ring , and for water sealing i use an simple paper gasket.

it may give you some idea for your engine :wink:

i start the test yesterday , it seems to work well for the moment :wink:

today , hard ride , and let see what's happen !!!!

so !!! , the ring do the job !!! full throttle on 6 gear for miles , the only way i know for testing !!!! :wink:



Click to expand...
Click to expand...

the other issue is the bottom liner seal, I use threebond 1207B and lay a huge bead 12mm diam around the liner above the sealing surface as well as a coating on the cases and of course the conventional selaing surface this is to provide some integrity to the seal and is suggested by JBS you can see behind these bearings that its quite messy but it does work 100% no issues

9362474679_d8c84bee4b_b.jpg


the other more elegant solution is to run small o rings as done by Contiman and Enginehardware.

the longevity of the piston/liner are good but 5.5 thou clearence is a bit loose IMHO 4 would be perfect.

with roller mains a 2206 on the drive side and an NTN NJ206 on the ign side with 1mm endfloat lasted 100 hours and stil looked fine.

now as a review this looks quite good but if i need a new kit i will organise it myself, much cheaper, closer to what I want and I won't have to wait
 
105mm CP piston (JBS)

330 hrs lots of sustained high rpm in the last 10 :D

16200199111_788d7532ac_c.jpg


drilled it ... lets see if it goes another 30 hrs while i organize a new piston and liner LOL
 
Last edited:
About time for a service yes :D

I was close to getting my hands on a 700 kit for my 570. But I was told that the former owner had completely ruined it and it was in no shape to save.
But I'm glad non the less, saves me loads of money and service time.
 
the liner already had 2 cut outs from jbs

yes the piston is good apart from the crack, ive done 8 hours already with the extra hole :)

going big can be expensive hey john but ... its awesome !
 
Perhaps it is amusing that to my untrained eyes that piston just looks charming and a little homey, some fraying never hurt a fine item!

700 kit for 570's? damn, what bore/stroke is that?
 
yes that is the correct description spanner :D

i was a little disappointed but 75+ hp for 300 + hrs compared to mid 50 hp and 30hrs from a 450 mxr piston puts it into perspective
 
berglsmerg said:
Ahh nuts to hp anyway, tq makes it go.
Click to expand...
This could be the beginning of a long and infectious discussion, that would totally hijack this thread! [emoji1]
1. I know exactly what engine characteristics you are referring to! A strong midrange [kW] is often desired aside from the drag strip.
2. The physical unit "torque" [Nm) cannot move anything or do any work at all. It's a static unit....

Any objections? [emoji1]
 
No not from me, maybe now your f#@)ing trailer is finished maybe you could make a new thread and school us a little more. Please? And then I can plague you with weird questions;)
 

Similar threads

thorgan
2001 FE501
Replies
0
Views
44
thorgan
thorgan
T
570 engine rebuild help!
Replies
5
Views
601
TurboYoda
T
thorgan
1996 FC600
Replies
0
Views
39
thorgan
thorgan
S
Steve's 2007 Husaberg FE650E aka Big Berg
Replies
2
Views
87
steve
S
B
Spark for 2-3 seconds then nothing.
Replies
10
Views
685
mosierz48
M

Register CTA

Register on Husaberg Forum! This sidebar will go away, and you will see fewer ads.

Recent Discussions

Recent Discussions

Back
Top