Honda CRF450R Throttlebody on 570.

Id like to try in the dyno where it does best. High rpm WOT Im guessing around 40 degrees will be good, from other engines with similar bore and chamber design thats where it usually ends up doing best.
These ecus seems pretty hack safe, which is a petty.
I think Ill give the stock unit a go and see what gives, fuel will be sorted with a bazzaz unit.
If anyone knows of alternative fully programmable units Id be keen to have a look at whats available.

Thanks Jon

Well if they do the job it may be considered a big wad of money but still cheap, avoiding sleepless nights

Got a bit further investigating this option today.
A friend just happened to have a 50mm honda TB laying around.

While having the tank off I checked what may eventually fit in there.
The honda TB is keihin too, but its not the same TPS and the angle the throttle wires comes out at is pointing straight at the cooler (have to make them bend pretty much)
I also happen to have a set of ducati 916 TB's (as Im a ducnut) and they seem a better fit for the goal. Upside with the ducati ones is they come with a proper stack plus theyre better shaped than the honda 2009 one as in better machined, throttle wire going up and not towards the cooler is a plus too. Downside is the TPS hysteresis wont go well with the berg ecu. Should be able to fit the berg TPS back on the duc TB, it seems possible with a simple adapter, just dont take my word for it though.

Either way its a lot of work for little return, may have to think it over for a while, just thought Id let you know my findings.
Looking at the oem setup the TB without butterflies flows equal to my heads now, BUT rule of thumb is to have at least 20% headroom for the butterfly, so in theory its too small at 42mm...bugger right The bigger size itself wont help much but the intake shape will benefit in my eyes.
This could well mean I have to leave the comfy sofa and actually do WORK, yikes!

Asking again may lead you to a nutter of range you wouldnt expect.
The obvious choice was there all the time, I just wasnt expecting it to be.
FP-engineering, converting ducati tb's to fit the 70 degreer.
I know ducatis and I have my 570 = match.
Decent pricing and seems to be a total nutter, which is top grade in my eyes

Any experience from dealing with him?

Thanks and Id be in shock if it wasnt a perfect record, same type I am in the ducati world from what I can tell.

tourist said:

I hope it's not too off-topicy - What would you ballpark a good throttlebody size for a "stock plus" motor? I.e. most things stock, just opened up a bit, e.g. exhaust / airbox, basic mapping?

Click to expand...

Asking me I assume? Id say it depends on what engine character you are looking for?

When husaberg developed these engines top end was never a goal, not even on the 450 it was, and perhaps the 570 should be best considered a blown 450, as they never raced the 570, meaning its not optimised at all, its just the big bike in the range for the public market.
Me personally, with the oem setup I wouldnt mind having a bit less bottom with a bit more top end.

Going for a different TB with a different size intake blade requires a range of things to change along with it, you need to machine the head to fit, mapping will be totally different as more air will slip through for a given degree, a few more things aswell.

Very hard to give directions unless youve done dozens of them, and I certainly have not

As I already have this thread going Ill just keep on writing here rather than starting a new thread to make a few comments.

With a bit more investigating I finally ended up with fp-engineering and getting the TB he does from ducati MS4RS throttles to fit the 570, all I have to do is steal the injector from the OEM throttle body with its mount along with the TPS and ship it there and he will return the new TB in a week or so.

Up and until now I have used the OEM ecu with a bazzaz piggy back unit for fueling, while at it with FP I will get the fully programmable ecu too.

Worked perfectly, flawless. Easy understandable user interface.