Well, I have heard lots of good things about Byrons.. Would run it if I could..

I guess in the States you can order and have it delivered by post too. Not here though.. (for sane prices as well..)

OK, so richened my HSN 2 hours. This obviously lowered the temps (210 degrees) but the motor still cuts in and out when I am near top speed. Again, like its topping out or hitting a redline... Any other suggestions?

It has to be your gearing. Try going up one on the clutch bell.

At my track I hardly get to 3/4 speed so I dont think gearing is an issue. I only hear it during tuning when I reach top speed. Just wondering if it is this normal to hear the engine cut in and out like a red line rev limiter in a car does?

No it is not normal for that to happen. To me it sounds like your engine is too lean on the HS needle. As you are only running 210 though I'm guessing that you are running a richer bottom end. So please pull your reducers and re-set the idle gap to roughly 0.5mm. Then put back reducer, set HS and LS needle to flush and fire up the engine. Blip the throttle for a minute or so to keep the engine running and to warm it up then let it come down to idle. If the idle is off do not touch the idle stop screw anymore! If the idle is low lean the LS 1-2 hours, blip throttle, let come back to idle and check again. Keep doing this until you get a smooth, steady idle. If the idle speed is too high you obviously do the opposite and richen the LS.

Once you have the idle set just put the car on the street and run it around for 3-4 minutes to heat saturate the chassis. Then do a high speed run then come in. If you need more top end lean the HS needle a few hours and repeat until you are happy with the top end then come in one last time to re-set your idle. Once again do this using your LS and if the idle is high simply richen the LS a few hours, blip throttle, let come to idle and repeat until you have a smooth steady idle. Once you get that done your engine is tuned and you are done! Give this a shot and let me know what happens.

One LHS only carries the Morgan fuels 30% strike team or 20% race blend, the other LHS only carries Traxxas Top fuel.

I was traveling today and stopped at another LHS that is a little over an hour away and they had some Sidewinder Worlds Blend 30% nitro 11% oil in a gallon. Unfortunately they are priced quite a bit higher than I am used to, paid more for it than the Strike Team by almost $10, but thats as close as I can get to what was working for me before, so I am going to give it a try.

I would not doubt I am off on tune, I had someone else with more experience helping me as well, he messed with it and it started to act lean (high idle after running) When I got home I richened up the HSN about 4 hours and leaned the LSN until the steady idle went high then richened for a steady idle. So I THINK the bottom is OK, if I lean it anymore the idle goes up. Ran it around for 2-3 minutes and it was at 240 degrees and I was down to a 1/2 tank. The overall smoke is definetely less than the old sidewinder, but still has a light trail thru the rpm band. I am baffled it can run thru that much fuel and be running hotter than before.

Tonight I am going to pull the motor, clean everything up, check the head and plug, and replace my clutch bearings. Hopefully everything will look good, then set the idle gap and needles flush and try to tune to the Worlds Blend. If that doesnt work I am going to beat my head on a wall..... wish I would have been able to just the the same fuel, it was working so well.... oh well crap happens.

Thanks for all your help.

No worries, just don't go crazy tearing your engine apart or anything like that. There is nothing wrong with it, you are just off on tune. The best thing that you can do is re-set the idle gap, set LS and HS to flush. Fire it up and set the idle using LS then run it and adjust the HS to give you the top end that you need and then re-set the idle one last time. From how you are talking in your post you seem to be getting the tuning down so this is not going to be very difficult for you and you should be bale to get it all done in 10 minutes or so. Give it a shot and see what happens. After doing this if your run time is bad then it's the fuel.

I am still pretty new to nitro, I have had them for a while but only race nitro 3or 4 times a year. So not much actual working time with them. I have been reading alot of your posts, I appreciate your support. I have been very very happy with all 3 of my Werks engines... two B5's and one B6 Pro.

Up till this fuel they have been so easy to tune, and ran so well, this is driving me crazy.

I mainly want to pull the engine to replace the clutch bearings (maintenance) they have been in there a while.

Thanks Again

i ran to tanks with race gen two 30 with 11 oil my plug is brown is this ok? and can not get the plug back out. it was gum up some?

my B5 is back!
 

double post

my B5 is back!
 

Well I couldn't wait so I flushed my needles, idle gap was good. So I filled up my tank with the Sidewinder 30% 11% Worlds Blend and fired it up. Let it idle with some throttle for a minute. When it got to 150 I started to lean, finally got a good idle going (needle is in further than my other B5 by almost a full turn?) then started to run around warming it up and leaning the hsn. After 5 minutes I felt everything was running pretty good. Refilled tank then ran for 4 minutes, engine was up to 205 degrees and still had over a 1/2 tank!

Looks like I am back on track! Looks like I may still have a little extra smoke going on, will run it rich for a little while to get her lubed up good.

Now I will replace the bearings, clean it up then do some fine tuning.

I dont want to give the impression the Strike Team is bad fuel, many of the fastest guy at my track run it and highly recommend it. I think it was too sensitive for me to tune and I just got impatient and frustrated.

got my box to work now thank you she runs like a top . got two tanks now and . do i put some more speed in it from a 1/4 on the gas

Brown gummed up plug sounds rich..... If it was that rich it may have had the cylinder full of fuel and locked it up, not letting it turn over with your box.?

As for plug being stuck, I usually put a tiny amount of anti seize grease on the threads.....I don't know if that's bad, but I figure a tiny amount only on threads shouldn't hurt. Maybe someone more experienced will chime in.

i let it sit a day or two after i ran two tanks. its a new motor with just a 2 runs on it still in the run in part.

Well I may have spoke too soon...... went racing last night and half way thru the first qualifier my engine would die sporadically, usually after a fast section then braking into a corner. So I figured my clutch was acting up.

I pulled the engine replaced the clutch bearings, checked the shims etc....all looked good....second qualifier same thing, engine would die after running at a high rpm then slowing down.....threw in a new plug checked idle gap tried tuning this thing for over an hour until the mains....mains came and still the engine was dying....engine temp was at 215 degress

After the races I messed around, setting the idle lean for a higher idle....extra rich and leaning the top and richening the top...all combinations I could think of, I got pretty frustrated to say the least..... finally set the idle gap to 1mm, and flushed the needles and retuned....that was the best solution I could find. After opening up the idle gap and re-tuning I ran thru 2 tanks with the engine only stalling out once. By then it was 1am and I needed to go bed.

Any other suggestions or ideas why I would have to open the gap up that far?

The repair tech from the LHS was there with me last night and he was puzzled as well, he said had some triple 7 sealent at the shop, so he took the motor home last night to seal it up... I am planning on installing a complete new clutch bell, shoes, springs, shims and flywheel just to be sure there is nothing going on there.