Rod length/ Compression Heights/ Case Heights

Hi All,
I am toying with the idea of destroking my 650 back to a 550 but need to know if this is viable.

I need to obtain the rod lengths, piston compression heights and case heights of the new generation vertically split engines in all their variants to ascertain if I can destroke the 650 with the 550 crank but retain my cases and compensate for the stroke decrease with rod length and piston height?

Does anyone have info on the above heights / lengths???

Cheers,
AUSBERG

Thanks Taffy.
From what I understand Husaberg may have offered different compression heights on the 100 mm piston

different rod lengths for the 450/550/650 as per. info in owners doc for 400/501/550

and different case heights to top it all off !!!!

Sure makes my 650 to 550 conversion either very very simple, or very very hard.

I should have bought a 501 in the first place............

Correct Taffy,
The parts manuals are indeed an invaluable tool for parts comparison.
Referencing the parts manuals was the first thing I did prior to posting this subject.
Whilst they did indeed confirm the different part nos. for all the components/capacities I listed, that is all they they did.
As far as any real technical information in regard to lengths/heights, I have put my faith in Husaberg owners/dealers worldwide who utilise this site.
I understand there are people out there who spend far more time/effort than I do with the Berg in pieces, and who have a much greater data base on the requested info. that I do.
I have no problems with posting a dopey question. I do it all the time.
I really appreciate it when my dopey questions attract intelligent, factual responses. I dont have a problem getting put in my place by people who can answer my query as I requested

That is why I consider this site an invaluable tool for all..
Cheers !!!
AUSBERG

benk said:

Taffy said:

you can check out a lot of stuff by looking up the parts book. i get lazy sometimes and ask dopy questions because i can't be arsed to check up.

i soon get put in my place though!

the 470 has the highest compression of all the 100mm pistons. but remember-that doesn't make it a bolt in item. time for the plasticine i reckon...

regards

Taffy

Click to expand...

the owners doc only has rod lengths for four models, no stroke lengths, no bore diametres, no piston crown heights and no crank centre to deck heights so the question isn't "dopey" it simply asks for help in clarification.
to answer without the aid of the technical detail; be careful not to run a short stoke very long rod combination. the intake charge can stall at lower rpm necessitating the use of intake and exhaust ports that you can fit your hand down. the resulting engine will be peaky and torqueless. on the other hand the opposite combination can lead to stratospheric piston acceleration leading to excessive rod stretch necessitating massive rods to avoid rod failure. if i get the detail i will try to sort out some combinations. some may require either piston or crankcase deck height machining to affect the fit and i'm not sure how much room there will be to play with.

Click to expand...

So then Benk,
You are saying that an off road ie torque orientated, broad rpm spectrum motor is far better off with a lower rod ratio overall than the equivalent stroke motor fitted with a longer rod to compensate for percieved, not proven taller 650 cases. Yes ?

This is all starting to get way to complicated for my feeble little mind.

Think I'll just leave the 650 as is and ride the KTM 300 2 banger instead.

Shame but.............the 550 probaly would be a sweet bike overall.