Husaberg Conrod Crank and Piston Dimentions.

Hi

I am new to this forum and to Husaberg motors, I am an engine builder in the UK and I have just taken on a Husaberg project. I specialise in big bore engines and will be taking the 2003 FE 650 motor that I have out to 750cc. I propose to do this with 105mm piston, 86mm stoke billet crank, new liner and any machining that is required. This may sound extreme but I’ve done single 900’s before so I’m sure its doable.

I need your help! I am busy with other projects at the minute and don’t have the time to strip and measure the Husaberg for a few weeks but I would like to get some of the parts on order with suppliers. I need to know the following for the 2003 650.

Con rod Centre-to-Centre distance?
Big-end pin?
Little-end pin (20mm)?

Piston compression height?

Deck height?

Crank case ID?
Crank max OD?

If you can answer any of these I would be really grateful, it will help me to get a kick start on the project and get my thinking cap on before I get my tools out.

Thanks

Ben Ballard
JBSracing

Dale

Thank you very much, this will keep me amused over the holidays.

I have been reading as much of this site as I can get through each night. It is with out a dought the best and most comprehensive site I have ever seen on any engine or bike.

From what I've read I think the counter balancer is out and I'll put bigger mains in if there's room.

I case anyone is interested the engine is going in a sidecar, www.sidecarcross.com gives you some idea. Sidecarcross is much bigger in europe than the states. I will post some pictures of the piston and rod I'm using here soon as I have these already, and will update with pictures of the crank etc as they arrive.

I read a reference to a Belgium 730cc Supermono Husaberg any one know any more about it?

Ben Ballard
JBSracing

Yeah I have seen a few teams at sidecar races in europe running Husabergs. There were two teams running standard 2004 650's in the GP's this year I took a good look at them.

The problem with 2004's and up is that the inlet manifold is cast on to the head! With the existing chassis/frames for sidecars there is no option of having a top tube air box like the Bergs. We chose a 2003 so we were able to cast a new rubber at a slight angle to get the carb fitted. This has worked out great, we have an almost straight line of sight from a huge air box through the carb' to a custom cast rubber boot of about 1L capacity and on to the inlet we made. Kind of a plenum chamber. Hopefully this will flow better than the fabricated and very small aluminium manifolds on the sidecars I've seen.

Perhaps the solo Husabergs would gain power from a conventional air box and straighter inlet tract?

Do you know any details of the 730 Husaberg? Bore, stroke, what broke when it first ran?

Dale a question for you?

Is 13.2mm compression heigh from the top of the pin to the top of the piston i.e. pin centre to top of piston 13.2mm + 10mm = 23.2mm?

Didn't really sink in at first, but I tried to draw it on CAD and realised that the piston crown would be rather thin if 13.2mm was from the pin centre?

Thanks

Madero

Thanks for the info' I did a quick calc' and by my reckoning if the stroke is 10mm bigger than standard i.e. 92mm the bore for 730cc is 100.5mm. As you say about + 10mm I am guessing that the about 730cc boys are using a standard bore after market piston and getting all the cc's on stroke? Thanks again.

Dale

Thanks for all your patient question answering, you are a mine of info' on Husabergs. I took a look at your gallery and it was most informative. The good mr. schwim has set me up a gallery and I have put some picies on it.

The 2003 650 came with a 39mm Delorto, I am going to put a 42mm Mikuni pumper on it as we want the pick-up out of corners the pump will give and bigger venturi in view of the 100 extra cc's. This is a good idea right??

Right my picies.........

1) Side view of 105mm piston - compression height 28.9mm form pin centre to top - 5.5mm taller than standard berg.

2 & 3) Top and Bottom, rings and 24mm pin.

4) Comparison of a 20mm pin to 24mm pin (20mm in picture not a Berg pin) - Note the Spiralocks next to the Circlips. Spiralock are much better they never break!!

5) Piston on Rod - a total of 12.5mm taller than stock. Compression difference 23.2mm - 28.9mm = 5.5mm + 5mm Long-rod + 2mm Rad increase on stroke (86mm up from 82mm).

6) The Rod - I like longer rods keeps the side load and angularity down. Standard Berg max rod angularity 17.86 degrees, my 750mm with long rod 17.88 degrees

Thanks for all the help guys.

Pictures of my 114mm pistons in my gallery if your interested.