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Husaberg Displacements and Short Stroking

Joined Apr 2004
518 Posts | 0+
Arizona
Have been wondering why Husaberg made some of the changes in 01 which to me seem a bit strange to put it nicely. Usually I'm supporting the Bergs, but on these matters I find it difficult. First, why are they running a 100MM piston in every displacement? Seems as ridiculous as Bultaco using a 60MM stroke on every motor size. We all know where Bultaco ended up. A 100X57 ratio is more severe than what the World Superbike Twins are running. Ducati Engineers have expressed concern about efficient combustion in the resulting thin combustion chamber that is required with these extreme short stroke motors to get a high compression ratio. If Ducati doesn't want to dive into this arena with their expertise it seems ludicrous for Husaberg to do so. 450 Ktm's use a 95X63 configuration on the MX model and an 89X72 on the EXC. The stroke on a 450 Yamaha is around 64MM FYI. Sometimes I wonder if the hard starting nature of the 470 and 450 Bergs doesn't revolve around these basic engine bore/stroke designs. Second, any motorcycle publication that did 500 class tests on off road/enduro models usually felt the snappy power of the 501 limited it's overall appeal and favored KTM or VOR powerbands, although the expert guys loved it. So.... what does Husaberg do? Use that 100MM piston and make the thing higher compression and even more radical. :? This also only added to the electric start problems. Third, they seem to have all but lost the MX market. Guys that run the bikes WFO and rev to the next corner to save a shift were losing the balancers. Who would want to repeat that problem on the next bike?

Well......would seem that Husabeg could do better by returning the 95MM piston for the entire 450 line and using a 63.5 mm stroke (Funny, that would duplicate what Yamaha did). In the FE only, bring back the 501 by using the 95MM piston. (Let a 550 remain in MX form for the power fiends and leave the 650 displacement alone in the various product lines.) Should also do what Dale is doing and leave the balancer out of the MX bikes. Motard could be offered in a balanced FE style motor for the street hooligans, and an unbalanced MX style motor for the racers. Heck, maybe even bring back an unbalanced MX model with lights and wide ratio tranny for desert racing and call it an FX again. If the FX line makes too many products, just put a 6 speed and lighting coil in the MX models like they used to do. This could all probably happen if the bean counters wanting to standardize parts/models would stay out of the way and let Husaberg breath. They sure don't restrain KTM at all. Putting forth some major effort/changes is probably the only way to get Husaberg into the big times. Heck, maybe KTM doesn't want that.
 
dsducati said:
why are they running a 100MM piston in every displacement? Bean counters wanting to standardize parts/models.

Putting forth some major effort/changes is probably the only way to get Husaberg into the big times. Heck, maybe KTM doesn't want that.

Hello dear friend,
I butchered your original post and as you may clearly see you have answered your own questions.

The standardized 100 mm bore is particularly foolish regarding the 450 as my 97 mm bore 448 is far superior to that of the OEM producing more than enough useable power to run with best GNC equipment. Said combination will also survive an entire season of top level competition.

For the record: My 448 design was offered to Husaberg in 2002 with the 2003 AMA Redbull Series as a target. Sorry, no takers.

Regarding monster hit and little else:
Camshaft profile (another graduate of the one size fits all institute) is partly responsible as is the selection of a poorly tuned, relatively small bore, flatslide carburetor featuring a non linear linkage.

Note:
Senior engineer Urban Larsson (my hero) whom brought you the Husqvarna and Husaberg engines left the company sometime after KTM came on board. Urban is now employed by Highland Sweden. (ie Twin cylinder Husaberg?)

I love Husaberg bleeding yellow and blue, however, in the end I call em as I see em.

Welcome to my world. :D

Sincerely,
Dale
 
It was a sad day when Urban left Husaberg. Same magnitude as to when Taglioni passed on and Bordi left Ducati. The decisions these manufacturers make. :roll: Dale, Keep up the good work fixing things.
Dan
 
This is a topic I have thought about for a while. I have always been told that an off-road engine should have a long stroke.


Highlander

The idea and intention were good both. Today you have the KTM 950 but it's heavier than V2 Outback. The new bikes I don't know anything about 'cause you hardly see any at all.
 

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