[varium]

No, Im not sure but in the process of elimination we changed plugs, coils, CDI, ECU, map, baro and 2 types of fuel during testing. It acts like the flame is being blown out but we just cant find anything wrong to cause that. The A/F curve does not show the bike going lean up top but due to the dyno's gas analyzer delay it may not show up under our circumstances.

The only thing that did help was to lean out the A/F to 13.5 or grater also leading toward fuel starvation problem.

I also have reason to think my fuel pump my be marginal but I forgot to take my spare with me.

Are you running one step colder plugs by chance?

 

[dstewart]

At first I was, but then we put changed them back. No difference.

 

[dstewart]

Last photo for a while...

Took it gently around the track a few times but until I get the top end sorted I was at part throttle and short shifting the whole way. It felt good just to parade it around though.

 

[AVR89]

Looks good. Nice and clean!
Good job

 

[irishaggression]

hey did you try Yu about the hrc fuel pressure regulator

 

[dstewart]

Update,

Found a new HRC regulator sitting around at a members house (Thanks Jason!). New fuel pump should be in this week. I sent my injectors off to RC Engineering for testing and balancing. I had two injectors in the low 280 range and two in the mid 290's. Now all 4 are 295 or 296. I'm also re-adjusting the valves after break in. The intake valves where a little tight for my liking at .004" and .005" (will be set to .008"). My goal is to have it back to the dyno next week to see if the problem was indeed fuel related. If not, I have more valve springs to try, HRC ECU and a few other goodies.

 

[dstewart]

Cleaned injectors in, HRC regulator in, new fuel pump and filter in, rear cylinder valve clearance done, I am waiting on three shims for the front (should be here mid this week). I don’t think I will have time to get it back on the dyno before next weekend’s race . Conveniently, four bolts and the front mounts just fold over as an assembly! Makes getting to the front cams a breeze!

 

[RC51Stunna]

Daamn Damon,

The amount of work you have put in is amazing. Way to pay attention to EVERY important detail.

I look forward to the time when I can start my engine work and electronics relocation projects. I will definitely be able to make use of your findings and hard work.

Keep up the good worK!

Stunna

 

[raceghost]

Jealous as hell! :rockon :clapper :woot:

 

[Redstar]

Damon if you dont mind me asking was it expensive to have RC flow the injectors? And possibly how much?

 

[dstewart]

No, it wasn’t too bad, about $25/injecotr. They flow them, clean them, replace the basket/filter and o-rings, then flow them again. When they are done you know exactly what you have. Even brand new injectors can be mismatched.

I spent some time on the phone with Rick Hobbs last night. As soon as I get the front cams back in (and new ignition pulse generator just to be safe) I’m heading to Erion Racing’s Dyno for the day. If the problem was not fuel starvation related we still have a few ideas.

 

[Redstar]

Thanks Damon, and good luck on the dyno hopefully you guys figure out the problem :clapper

 

[varium]

Update,

Found a new HRC regulator sitting around at a members house (Thanks Jason!). New fuel pump should be in this week. I sent my injectors off to RC Engineering for testing and balancing. I had two injectors in the low 280 range and two in the mid 290's. Now all 4 are 295 or 296. I'm also re-adjusting the valves after break in. The intake valves where a little tight for my liking at .004" and .005" (will be set to .008"). My goal is to have it back to the dyno next week to see if the problem was indeed fuel related. If not, I have more valve springs to try, HRC ECU and a few other goodies.

At the bottom of the RC readout....just what are those numbers correlating to? I understand the 80% duty cycle and the estimated BHP a set of these size injectors is presumed to support, but that whole .65 .55 .50 thing throws me. Can't really makes heads or tails of it which makes me think i'm reading into this the wrong way. Did they explain to you what that all means?

 

[dstewart]

Yes,

See this page for more info then I can type. RC Fuel Injection

 

[mrgrn]

nice man, just nice!

 

[dstewart]

Yes,

See this page for more info then I can type. RC Fuel Injection

Running the calculator at the bottom of that page I'm thinking fuel starvation is/was my problem. We hit 144 at the rear wheel x 1.12 for frictional losses = 161 BHP. At 50PSI that would require at least 270cc/min for a B.S.F.C of .55 (its slightly higher because of the fuel we used). The VP (similar to U4.2 but not) fuel requires about 8 to 10% more volume then pump right off the bat so if my fuel pressure was to drop any I would run in to problems. The HRC regulator will bump up the fuel to 57PSI at idle and I have a new fuel pump with clean and balanced injectors. I hope that takes care of it. I will know for sure next week.

 

[varium]

Now all you need is a fuel pump map. Would probably be no problem as i think some turbo bikes still use the stock pumps for moderate power increases, but the more you build fuel pressure there comes a break point where the volume tapers off. Don't want to run into running high pressures and end up with a lean out due to decreased volume.

 

[Cutaway]

Running the calculator at the bottom of that page I'm thinking fuel starvation is/was my problem. We hit 144 at the rear wheel x 1.12 for frictional losses = 161 BHP. At 50PSI that would require at least 270cc/min for a B.S.F.C of .55 (its slightly higher because of the fuel we used). The VP (similar to U4.2 but not) fuel requires about 8 to 10% more volume then pump right off the bat so if my fuel pressure was to drop any I would run in to problems. The HRC regulator will bump up the fuel to 57PSI at idle and I have a new fuel pump with clean and balanced injectors. I hope that takes care of it. I will know for sure next week.

Bingo brother.. that is what I told you on the phone last month... I enjoyed our conversation the other night, call me as soon as you get to LA.

Cheers! Josh

 

[dstewart]

Left the house at 4:30 am, arrived at Erion Racing at 6:30 am met with Kevin Erion and got the nickel tour. Met with Rick Hobbs at 8:00 am and proceeded to pay through the nose to have my bike re-mapped after changed the fuel pump, filter, HRC regulator, flowed and cleaned injectors, new plugs and a new PC3USB. Left Erion at 4:00 pm very, very satisfied although I've lost several ponds of weight out of my back pocket.

For the results see this link
http://www.speedzilla.com/forums/rc...finger-emoticon-when-you-need.html#post513093