2011 CRF250r throttle position sensor TPS set up?

Hi lads, got a 2011 EFI CRF250r that is a real pain to start. Basically has had an engine rebuild but the thing is really difficult to get fired up. Had new wiseco piston etc, all the timing is spot on along with the valve clearances.

Had the fuel pump out too and works fine with 12v on it, the only thing I'm unsure about is setting up the TPS on the throttle body, has anyone got the proper procedure or theory for the correct position this is supposed to be?

To me its like the bike is not getting the correct fuelling to start when I'm kicking it, what is the right procedure for starting these EFI bikes? I don't have the owners manual just a workshop one but it doesn't give you the correct starting procedure in it. Tried all theories with 3 kicks to charge and prime on full throttle then closed off throttle to try and fire the bike up - it goes eventually but man it must be easier than this!

Any experiences would be greatly appreciated

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You can test the TPS theory setting it free hand. Mark where you at now and then loosen the set screws to where they're just snug and you can move it by hand.

Then go to extreme in either direction.

 

It would be nice to know where your at to begin with.  All you need to do this is to tap into the measurement wire with the red wire of your multimeter and then connect the black wire to ground. With the engine running the oem numbers are usually around .47v - .49v. Unless someone messed with it. I have a 12 that runs beautifully at .51v and a 13 that wants .61v. I don't remember which wire is the measurement off the top of my head so search this forum. There was a lot of discussion a short while ago. With a lot of good info.

 

Actually that discussion was in the CRF450R forum.

Edited by nesc103y

Yes, that's a good method for 1-time setting/testing.

Sounds like your 2013-450 simply needs a (richer) re-map (Vortex or OEM ECU, doesn't matter) as .61V is waaaay too high, so you're just enriching the entire operating range by doing that and would then be lean on top. The 2013 comes with a pretty lean map and needs more fuel than you think. That's why guys that bolt on any aftermarket "richer" box thing it's the best thing since sliced bread.

Edited by Eddie8v

Yellow wire with green stipe is the one you want to tap into, check while bike is running on its own power , that earlier thread was started by me asking same problem after rebuild with wiesco piston also, what temp are you having start problems with , real cold ? My bike is a 11 also !!

Lads, thanks very much for the replies, much appreciated and some good info for me to go on.

TPS is sitting about mid point at the moment ie securing bolt has equal adjustment either side of it.

It's hard to start from cold, once its running not too bad to get going again - had a few 4 bangers in my time but this is my first EFI one. Up to now it has kinda put me off fuel injection bikes but suppose they're all going this way so just have to adapt!

Any you guys know what Honda quote on starting method from an owners handbook etc? Can't find this info anywhere online and not buying a handbook just find this out. Bought a workshop manual for the rebuild but doesn't have any info about proper starting techniques?

Cheers guys

I have the same problem with my 2010, hard to start cold, not too bad when warm. Rebuild made no difference, valves in spec etc.

Spoke to a guy at the track last weekend with the same model bike, his starts first kick!!!

I bet his bike don't start first kick when it's frikin cold , my bike starts

On 3 when it's like 50 or 60f first time of the day and after that it will start first kick for the most part but when it's like 30f or so it's a nightmare and I dread it , but try this , give it a couple lazy kicks to charge capacitor and then pull the enricher knob out and give it a few continuous rapid kicks , if it fires up don't blip the throttle to soon as fuel pressure may not be built up fully and it might die out on you and then it will probally have a wet plug like its flooded out and become a b$&@$ to get fired up , I have a 11 also and go thru the same crap in winter , a remap is in the near future with Eddie S. and Eddie if you read this I would like your take on these issues all of us are having thanx!

Just would Like to add that if you don't have a meter hooked up , just loosening the screw will change your setting (very sensitive) , I wish I would have never touched that damn thing , always has me second guessing even tho it's set to .50v good luck I learned my lesson!!

Just would Like to add that if you don't have a meter hooked up , just loosening the screw will change your setting (very sensitive) , I wish I would have never touched that damn thing , always has me second guessing even tho it's set to .50v good luck I learned my lesson!!

 

 

This is absolutely true. you can't judge the setting by the spacing on the set screws. That can only be used as a ref point.

Checked mine today, was at 0.46V, adjusted it to 0.50V. 

Surprised how fine the adjustment was, will see if it starts easier tomorrow.

 

also modified the idle screw to block off the end

Would like the results on idle screw mod and now that my tps is at .50 seems like it want throttle cracked a smidge to fire up , does that mean its wanting more air than the idle screw was allowing ( to much fuel not enough air) ?

Put the bike back together today, yep still a PITA to start cold, starts easy when hot.

Valves are new Kibble whites and are in spec, has a Eddy map also.

Might check the valves yet again on the weekend to double check they are still ok, I have also noted the decomp is very rattly when first started until you rev it for the first time, is that normal?

does that 04 decomp mod suit the rule injected models?

 

also has a hotcams 2 fitted

took bike to the dealer today, will see if they can fix it

Report back with your findings

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