Need advice on fueling

oneupmotogarage

New Member
First post on this forum, hey everyone!

I'm just starting a custom RC390 for a client and this is the first FI KTM I've messed with, so I am looking for some specs on the fuel delivery system. I'm not running the stock tank and I can't graft the pump assembly into the custom tank due to its size and shape. So I'm left needing to run an aftermarket pump and FPR. The pump I'm not too worried about, I plan to just run a small high pressure one. It doesn't need to put out more than about 50psi correct?

My main question for today is about the FPR. It is built into the pump assembly in-tank, yes? Is it liner or does it adjust based on intake vacuum or input from the ECU? Really hoping vacuum, or linear would be nice but I don't expect it is. What are the bar or psi specs for the stock regulator with bike off/ idle when warmed up/ and under throttle?

My second, somewhat related question is about tuning. I'm running a K&N filter and a hand made exhaust to some Lossa Engineering mufflers. So it will need a piggy back programmer, which would be recommended for this type of mod? I've heard mixed reviews on the "autotune" ones. I can have it dyno'd and a map made for it but just want to know what hardware would be the best to work with on that. I do plan on keeping the header stock with the o2 sensor location untouched.

Hope this is a good place to post these questions. Thanks so much to anyone who reads this and has some advice/ info!
 

zaster

Member
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I'm sure you know that OEM motorcycles are tuned for minimal emissions and are therefore running lean. This means that your engine runs hotter with reduced power.
Get the DynoJet PCV with the WBC2 autotune and you will be happy. Ask me how I know.
 

CDN Duke

Member
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Hope this is a good place to post these questions. Thanks so much to anyone who reads this and has some advice/ info!

hey Taylor, checked out your site - look forward to seeing what you come up with using the RC390 as a base!

just FYI, you've posted this in a forum supporting vendor's sub-forum.... KTM Performance is a shop in Louisville (Commonwealth Motorcycles) and while I expect Chad will know the answers, your questions may be better placed in the Engine and Technical sub-forum, here: http://www.rc390-forum.com/forum/forum19/
 

oneupmotogarage

New Member
Awesome thanks I'll paste it over there and see what happens.

Not sure how to delete this thread so maybe a moderator can do that for me.
 
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