barrel has wavy lines top 'n bottom

Husaberg

Help Support Husaberg:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Nov 20, 2001
Messages
17,028
Location
Ely, England
when rebuilding my engine i noted that the barrel/spigot/lining or whatever; had ripples at the top and bottom but badly at the top?

i trust this a nikasil lining these barrels have? only i had about 10 barrels on the ducati F2 i raced and there was NEVER a mark or a notch!

it was air cooled BTW and ran tighter piston to linar and ring gaps than the water cooled berg. progress!!!!

they were like brake bumps on a MX track. about 5 at the top and 2-3 at the bottom. underneath where the rings stop was almost a discernable lip. i didn't measure it as i couldn't do much about it-in a rush to rebuild it.

also the brand new little end bush was sloppy.

lots there for you techno freaks... :idea: :idea:

regards

Taffy
 
That does not sound good at all. You are going to replace it right? As for the reason for it I havnt got a clue. All the liners I have seen had nothing more than some slight verticle scuffing (except in the case of major failure).
 
Hi Taffy,

The plating is quite thick (.5 to 1.0 mm).
Ripples are often the result of a loose slipper piston (ie short skirt) combined with excessive clearance and / or detonation.

The 20 mm big end bushing always spins even with purpose adhesive and / or burnishing. The thick wall 18 mm bushing rarely spins unless it siezes to the pin.

If you are spinning an 18 mm ID small end bushing chances are your small end rod bore is no longer round. (ie hundreds of operating hours, sustained excessive rpm and / or detonation)

Hope this helps.

Kind Regards,
Dale
 
the new LE had as much slack as the old one and that hadn't been spinning.

i can quite believe you on the 20mm LE-it has far too little material.

i have checked the plug and piston for detonation and i haven't had any. however the piston is on it's maximum clearance. 91.78mm or something like that. it's got to get me to the winter when it will get about another 10 bearing, a rebore and a new piston.

while i'm here is it possible to reem out a 18mm LE to the new 20mm LE size for a 450/470 piston?

regards

Taffy
 
Taffy said:
the new LE had as much slack as the old one and that hadn't been spinning.

i can quite believe you on the 20mm LE-it has far too little material.

i have checked the plug and piston for detonation and i haven't had any. however the piston is on it's maximum clearance. 91.78mm or something like that. it's got to get me to the winter when it will get about another 10 bearing, a rebore and a new piston.

while i'm here is it possible to reem out a 18mm LE to the new 20mm LE size for a 450/470 piston?

regards

Taffy

Hi Taffy,
You do indeed intend SE as opposed to LE regarding the small end bushing do you not? Is it possible I have goofed yet again regarding special motorcycle jargon. :roll:

All Husaberg small end rod bores are of the same ID.
Your engine being a 400 will use an 18 mm ID Bushing. All larger displacement engines use a 20 mm small end pin consequently they require a 20 mm ID small end bushing. All else remaining equal the bushing wall will then be one mm thinner and as a result more inclined to spin.

FYI:
Bushing spin is quite common on the larger engines with a 20 mm pin.

Kind Regards,
Dale

PS
Measure both the rod bore ID and bushing OD in numerous places. Note how easily either bushing (18 mm or 20 mm) distorts with just hand pressure. Imagine what it does in an out of round small end bore.
 
hi dale

we brits say 'big end' and 'little end' fella!

i got a new 20mm little end bush sent to me and it was oval when it got here! you're right!

rippled%20barrel.JPG


regards

Taffy
 

Register CTA

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

Recent Discussions

Recent Discussions

Back
Top