Timing Adjustment for Nitrous '05 CRF250R

I have a 2005 CRF250R engine in a 1994 Honda RS125 roadrace chassis I built for Land Speed racing at Maxton Mile. I added a small shot of Nitrous to it in Sep 2010 with great success. But as I start to add more this year I need to retard the timing 3-5 deg. Does anyone know how I can do that? Did I miss it in the manual? I use the stock ICM. Thanks.

You can. The only problem (if I can remember) you might have is that the holes are round and not adjustable like the older models so you may need to modify the stator to get the 3-5 degrees out of it. I'd do some research before you blow that engine sky high. 3-5 degrees may not be enough. Detonation with the NOS could be the end of that engine. Hopefully, you have a solid lower end also. That won't take much to destroy either.

can you get the ecm recalibrated? and do you want the timing retarded at all engine rpm or just wide open throttle WOT? Were you planning on having the nitrous activate at WOT only? I was also going to suggest rotating the stator but you probably already considered that.

I think Tokyo Mods has an ECM. Maybe they could make you a custom one or maybe Ron Hamp/Tuf Racing.

Thanks for the info Charlie and Keith. I will look into the Tokyo Mods and Tuf Racing. Didn't Vortex make something as well? I would prefer to be able to adjust it externally between runs rather than adjust the stator. I run this bike in gas class as well as the fuel (nitrous) so I would not like to give up power when just on gas. Just to reassure you I have a mentor in UK who owns and designs Wizards of NOS. He has said for my amount of NOS I only need 3-5 deg retard. Yes I only engage the NOS at WOT but I can live with the retard for the whole run rather than make it complicated. I have already made I think 13 nitrous runs safely and have blown away the prior records. I am the only Honda, but there are 2 Ninja250s running nitrous but their best is 122mph. I am running a HotRods lower end and a Wiseco 13.5 piston. I have added 15-17 RWHP with the NOS and so far the engine is very happy.

Again thanks for your suggestions.

Check out the ProCom Programmable Power Curve. I don't know a lot about it, but from what I understand, you can pretty much dial everything in including the rev limiter. I heard most of the units you are not able to adjust the rev limiter. Not that you'd want to, just the idea that you can and it has that much flexibility.

i have the vortex software to reprogram there ignitions it cost nearly $1000 several years ago if you could find some body over there that had it they could do the same also vortex may program an ignition for you.another option would be the 250 x ignition box it will have a softer curve about 4 degrees.you could switch boxes with fuels.

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