NITROUS OXIDE ( nos / n2o ) advice forum

Trev,
Order for the SS Braided lines placed a few minutes ago. I hope to convince the chief inspector that I can use the Nylon. I'm headed to the bottle filling station today.

Now new questions-
1. How do you regulate bottle pressure at the track? I understand that if it is a cold day a bottle heater is very helpful. But what if it is a very hot day, say 35C? I often have to sit in line with the bike for 90 minutes on a busy meet and we are 1 mile from the pits.
2. I may have the opportunity to do another dyno run before the September meet. I will do some runs without nitrous to check the engine 1st. Then is there anything special we should do to check the nitrous power addition?

It's finally alive!!! Well, my WON SB25 system and Max Extreme controller are finally installed on my Honda 250. I was able to get the NOS hoses and gauge all sealed using the advice on this forum in the How To section (Thanks Loopy!). It held pressure x 24hrs. So I moved on to the system test of the controller. It fires the pulsoids just fine so last night I did the static test. I warmed up the engine. I opened the NOS bottle valve, gauge reading 900psi, and armed the system. It idles at 1700, and redlines at 13100 so I held the throttle at 4400 and hit the button. It coughed twice then revved to 10500-11100 with some misfires while topped out on all 3 test runs. I videotaped the run. http://www.youtube.com/watch?v=bLXcv34mSBA
So the question- is that still slightly rich or just the right amount of rich? Should I get a single step leaner fuel jet?

Jarl
Sharpsburg Maryland USA

It's finally alive!!! Well, my WON SB25 system and Max Extreme controller are finally installed on my Honda 250.
GREAT news Jarl
Yeah, that accounts for my goofy grin on the video.

It idles at 1700, and redlines at 13100
That's a lot of rpm for a 4 stroke!!!
The CRF250R is an amazing engine.

http://www.youtube.com/watch?v=bLXcv34mSBA

Looks to be just about right for a first test run and then tune from the plug results after that.
okay, good. Do I need to order some jets to have with me at the track in 3 weeks? I will be able to check the A/F data after each run
Has it got a rev limiter on it, because it sounds like its hitting one?!?!?
It does have rev limiter but that should not have cut in until the 13100 mark. But I agree that it sounds that way.
I'm also rather surprised at your exhaust pipe, because I'd expect that to be more restrictive than a megaphone type exhaust arrangement.
When I researched exhaust pipe design this type of straight pipe with a diameter change was what was supposed to create a pulse wave at a certain rpm to help suck the exhaust gases out of the cylinder. So the length of the header and tail pipe are set based on the cc, cam timing of exhaust, and desired rpm for the best power. Mine is set for about 11,000. It really helped (along with other things) to jump my records by 10mph average this year! But it is also very loud and obnoxious.

Jarl

Maxton Mile WON September to Remember
I have enjoyed reading so many other teams' race and build stories on this forum that when my Nitrous Debut finally occurred and I had "WON September to Remember" at the Maxton Mile I thought I should contribute my update also.
I designed and built my initial Honda assault on Maxton Mile Land Speed Racing (LSR) back in 2008. I took a 1994 Honda RS125 roadracer, pulled out the 2-stroke engine, and wedged in a 2005 Honda CRF250R 250cc 4-stroke single cylinder engine from a motocrosser. I have changed it somehow for every meet since then. As I add and alter pieces it has slowly become as my wife calls it a "Science Fair Project." Since it is a road racer chassis it is automatically in the Altered class. So to take advantage of the class rules this past winter I designed and built a new seat/tail to try to improve the airflow behind me. It has definitely helped.
Two years ago I met Eric (Racer X) Roehrle. He is Dark Horse Racing with his Kawasaki Ninja 250. It is hard to resist his enthusiasm for this sport and we quickly became friends since we both lived in Maryland and we both raced a 250cc 4-stroke. The even better part is that since his is a streetbike it is in the Modified class so we don't compete directly. Well Eric and I were both whining about the fastest 250/4 (stroke) ever at Maxton which was 119mph by a Kawasaki on nitrous. It made one run. We both decided to quit whining and get busy and try to both run nitrous at the September 2010 meet. We both wanted to be the 1st 250/4 to break 120mph at Maxton. So we went our separate ways to do our research on the "scary NOS", "liquid horsepower", and "engine-killer". Eric decided on the BossNoss US system and I chose the Wizards of NOS system (of course) from England. I don't think either system had been used before at Maxton. I built a new gas tank to add a dual tap high flow petcock and also to lower my head in the tuck.

We were emailing back and forth and when I had my WON system installed I made a video of bike with a music soundtrack using "We're Ready" by Boston (noted in a prior post) http://www.youtube.com/watch?v=bLXcv34mSBA Both of us were like kids with a new toy under the Christmas tree. Now it was finally time for the meet. We park the trailer next to Eric's van, unload the bikes, and roll them over to the Tech line. Both bikes pass Tech so we breathe easier. But as I prepare my Honda for Saturday my first wiring glitch shows up- nothing electrical is powering up. I fear that it's a bad omen but I track it down to just the main battery lead sliding off the spade connector. Everything else seems fine again.
Saturday morning is beautiful but warming up fast. Small tailwind too! Eric and I both delay our Nitrous event a little longer. I need to first secure the last Altered 250/4 class record (A/G-250/4) which is naked and only Gas. So the fairing is off, the tank is sealed with track gas inside, and the Nitrous bottle is sitting forlornly in the trailer. I make my first pass down the track reaching 113.3mph on a 104.7 record. Eric wanted to delay the Nitrous for one run so he could first be sure of all the other aerodynamic changes he had made on the bike. They seemed to help as he went through at 112.2 on a 107.4 record for MPS/BF-250/4. Then I go to the trailer to get my bike ready for a NOS run by raising the gearing way up, adding the fairing, and then the bottle is slid into the holder hidden in the tail behind my right leg. Pressure looks good.
Finally Eric is the first to fire his Nitrous waiting until topped out in 6th gear at the 3/4 mile mark. His speed jumps 5mph to 117.4 making it the second fastest 250/4 run ever at Maxton. But he says it doesn't sound right. He quickly goes down and does another run but only goes 115.1 saying it still sounds off. Now I'm finally ready so we both go down to the staging area together. As I look down the almost 2 miles of open track I shake my head with disbelief knowing that we in LSR get to do what every driver like us wants to do when you are first in line and the traffic light turns green. I get the "Visor Down" followed by the "Track Is Yours" sign. The engine roars to life through the straight pipe exhaust as I make a smooth run up through the five speed tranny. Then at the 3/4 mile, with my heart racing, I push the little red button with my left thumb. Nothing changes. I push again. Again nothing. Noooooo! So I make sure my tuck is optimized and go through the trap without NOS at 116.0 on my APS/F-250/4 record of 108.4. My second fastest run ever, a new record, and yet I'm disappointed. No nitrous firing. But as I'm at the registration trailer getting my new record certified and wondering why the NOS didn't fire, Eric makes his next start. He is determined to make something happen this time so he fires the Nitrous sooner, blazes down the white line on his "Angry Bumble Bee", and I can't believe my ears when the radio announces his speed of 121.8mph!!! Eric has done it! He is the first 250/4 to break the 120 mark at Maxton! Dark Horse Racing rules all other Ninja 250s!
Meanwhile I go back to the pits and find a NOS controller glitch in my rpm safety window setting that I had forgotten to account for, rectify that, and once again I go down the track but again no reaction to the red button. But again the engine sounds very happy and I get a new Personal best of 117.1 without NOS! But again it is weirdly disappointing. All because of the Laughing Gas. I feel it is laughing at me, not with me...
Eric huge smile has not faded as he backs up his run with a 121.6. It is in the mid 90 degrees now so he parks his bike for the day. Now once again I am in the pits sorting out what I am convinced is a wiring disconnect. Then I stumble onto the problem. Since mine is originally a motocross engine, I have to run a battery as a total loss system to power the data logger, dash, cooling fan, and WON system. The battery was fine for everything visible but was drained enough by the controller switch being left on overnight to not be able to fire the solenoids to release the nitrous and fuel. So Eric to the rescue with a power convertor (which someone else had just given to him earlier this meet) to charge the battery off my roller-starter battery. Three electrical problems, all my fault, oh well. Wait 1 hour. Then riding gear back on, unplug the bike, and head back down to the staging. Almost no one there anymore due to the heat. Suddenly I'm at the line. Here we go again. I notice one of the ECTA volunteer staff using a Flip video. That must be a good sign I think. So off we go. Slip the clutch forever in 1st. Accelerate to 12,500rpm at 60mph, shift, repeat, shift, repeat, keep the tuck good, head down, toes in, knees in, elbows in. Then I'm in 5th gear...I think...forgot to count again....try to shift again...no, already in 5th. Here comes the 3/4 mile mark. Speedometer reads 117. Take a relaxing breath. Push the red button. Yeah baby! It feels like I just smoothly rolled on the throttle another 1/4 turn as the controller adds the Nitrous and fuel from 20%-100% in 5 steps over 2 seconds. Speedo climbs steadily and engine sounds happy and I have a huge grin on my face as I fly through the trap at 126.6mph!!! What a feeling!

I made one more run ten minutes later just before they closed the track for the evening and did a 126.5. Then Sunday morning I did one run but the exhaust note changed slightly and I found the pipe was broken at one of the 1st welds I ever made 2 years ago. Eric did 2 Sunday runs. His 1st was almost a match for his record at 121.4. But on his last run as he applied the nitrous in 5th and again in 6th at the 1/2 mile, his clutch was slipping and allowed the engine to hit 14,500 rpm losing power at the 3/4 mile mark and coasting all the way to the normal turnout. His # 1 piston had rings pinched in the groove and #2 piston was holed. Eric was the 1st 250/4 to break 120mph at Maxton Mile and is now the World's Fastest Ninja 250! But he also had to rebuild his engine.
I am the first person to ever earn an LSR D License (125mph) on a 250/4 and my Honda CRSF250 is now the World's Fastest 250/4 in Land Speed Racing. And my engine and plug still look very happy, just like me. Thank You, Thank you, Thank you!!! to Trev for providing a fabulous Nitrous system and the encouragement to make it work as advertized. Also thanks to all the folks at Maxton Mile that make it possible for us to safely have this much fun with these bikes that don't go 200mph. There is much more left to do with the help of this great stuff called Nitrous........

EXCELLENT report Jarl and I look forward to hearing how you do on your next outing.

Best of luck with that.

Well done

what a great write up.

Ever since the September meet success I had my buddy Eric and I have been on the Landracing.com forum hyping an October Nitrous 250cc Shootout at the Maxton Mile. It was held last weekend and here's the report.

Well the Maxton October Nitrous 250 Shootout was held under gorgeous weather conditions of sunny, cool air, and some tailwinds. Unfortunately the nitrous bottles don’t exactly like cold temperatures if you want the bottle pressure to actually push out some nitrous to join the extra fuel you are adding. We had all three of the expected 250s show up. Eric (Dark Horse Racing) on his Kawasaki Ninja250 using a BossNoss system and I (Moto Madcap) with my Honda 250 using a WON SB25 both made it through Tech Inspection Friday afternoon without any defects found. Since the September meet Eric had rebuilt his engine and clutch and added a new methanol tank to go with the NOS as well as a gorgeous new much more streamlined aluminum custom gas tank. I had repaired my exhaust pipe and added a WON bottle heater for the NOS.
Then we went out to dinner together and spoke eloquently about all the amazing merits of our bikes and just how fast they would be on Saturday ;-) Meanwhile Ali (RnR Cycles) was working feverishly in his shop all through the night to get his Kawasaki Ninja 250 built with a US Nitrous system installed.
Saturday dawned cold and clear with a mild headwind. I decided to wait for the afternoon’s warmth and expected mild tailwind. That way my bottle heater would not have to fight the 45deg cold and the engine would not have to fight the headwind. Eric tried to fire up his bike in the morning but it refused. Then we switched it to my DocZ roller starter and found out his Ninja also did not want to change into 2nd gear, like something was jammed inside. So Eric pulled his carbs apart and found something amiss inside. He had just finished rebuilding his engine from last month so he is very familiar with how it looks inside. But it still would not shift, so he pulls his engine completely out of the bike and puts it in the back of his van. There he splits the cases and carefully inspects the clutch and tranny. He finds some small pieces of metal, probably part of last month’s piston, one of which was jammed in the gears. So once that is cleaned up he reassembles everything. He eventually gets it fired up in time to make a run in the afternoon!
Meanwhile I work my way up to the line. Because of my inefficient last minute mounting the bottle heater can only get the pressure up to 800psi. I make a run with the engine sounding happy, firing the nitrous just before the ¾ mile mark and I put down a 125.1mph speed on my prior record of 108 in the APS/BF-250/4 class.
Eric finally gets to run his yellow Ninja at about 5pm. But on the run he said the engine kept feeling like the clutch was acting up. Then when he fired his new methanol/NOS it made a bang heard even in the pits. He said he had been up to 108mph then coasted through the trap at 91. The highs and lows of Nitrous.
Now finally Ali shows up with a new nitrous system on his old Ninja250 which he has also lowered both in the front and rear. He gets through tech inspection and rolls up to the waiting line but to no avail. Track is shut down for the night with both Ali and myself almost to the front of the line.
Sunday morning Ali makes his 1st run which he says is a shakedown to make sure the chassis is good and stable. It is and he briefly fires his nitrous with low pressure in the bottle and goes 117.4mph. An hour later he and I go again 3 runs apart. I have my fastest time of the meet at 125.5mph! Ali then goes through with pulsed Nitrous firing this time in 5th and 6th gear and goes through with new record of 122.0mph! This beat the MPS/F-250/4 class record of 119. Later in the day he did several more runs with his best increasing the record to 122.4mph.
So the Maxton Nitrous 250 Shootout came to a close with me retaining the title of Fastest 250/4 though I did not beat my track record of 126.6 set last month.
I am only using a 30 jet for NOS and gravity feed for fuel. My bottle heater I bought at the last minute and had to install it on the bottle holder since there was no room for it without a major change of the custom holder which I will do this winter. I was ready to increase the NOS jet to 35 or even 40 if the competition got faster. The bike with the Wizards of NOS system beats the US NOS bikes again even though mine is a single cylinder vs their twins.
I will post another Youtube video soon. Thanks Trev.

EXCELLENT news and as we're now starting to expect, a very well presented and interesting report.

Many thanks for that and keep up the GREAT work.

BTW I can give you a few more tips on the pressure side of things if and when you need them.

If you ever need to go MUCH quicker, then a REVO upgrade would certainly help achieve that, as it can be set to maintain the optimum mixture ratio regardless of pressure etc.

Here's a link for the short Youtube Video which includes a run through the speed trap at 125.5 mph from last weekend.
http://www.youtube.com/watch?v=g-GZ-glildo
Hope you enjoy it.

Excellent.

Sounds to be almost spot on mix, just a touch rich if anything.

What rpm were you pulling and what is your max achievable rom?

The Honda CRF250R engine redlines at 13,100. I went through the trap at 11,500 which is where the engine without nitrous starts to drop power on the dyno above that. I can go up one less tooth on the rear, adding about 5 mph for the same rpm. Beyond that I need a custom front sprocket which are more complicated to machine.



My bottle holder if you look at the pics of the naked bike earlier in the thread is a large sleeve with a clamp. I did not have time to modify this so I had to slap the heater to the holder metal and some of the heat transferred to the bottle but not efficiently. So I will need to make a cutout in the holder to allow the heater to go directly against the middle of the bottle. But without a large battery or generator I did not want to try heating the bottle up from 45degF although I heated it to 95degF before leaving the hotel at 7AM.

I did meet David Pike at the track and I gave him a thumbs up on the system, though he has already bought his I think.

Trev,
Just wanted to let you know that I was just interviewed this morning for 90 minutes by the Bonneville Racing News for a future article in their publication on my Nitrous Honda 250cc Land Speed Racing Record Holder. Of course I mentioned Wizards Of NOS!

What a good man you are!!!

Will this be a paper publication or some other kind of media?

Whatever the case I'd like to see it when its published.

Many thanks

Trev,
Bonneville Racing News is a newspaper published I believe for 20 years or so. It is mailed out 7 issues per year to a woldwide audience of Land Speed racers. I think I heard they have 2,000 subscriptions. The article with photos as space allows will likely be out in a few months. I will get you a scanned copy when it arrives.
Thanks again for your help this year. I could not have done it without you.

Hi Jarl,

It's very nice to hear my contribution has been appreciated and its always a pleasure to be of assistance to someone so appreciative.

I'll look forward to seeing the report and to assisting you to push that record even higher next year.

Hey Jarl. I was strolling through the internet and came across this site:

http://www.google.com/url?sa=t&source=w ... wd2ZpSh-Fw

Looking at the pictures it suddenly dawned on me. In my teenager years there was an active bunch of Dutch motorcycle racers competing in grand prix racing in the 50cc class back then. Watched loads of them on television. Some of them even used their expertise to construct streamlined racers for speed record runs. While they didn`t use nitrous like you do they achieved some pretty good results in those days.
Enjoy the pictures.

Paul.

Paul,
Thanks for the link. I had a blast looking at those pictures. I truly feel that with my bike and faired tail I have a significant advantage over the Kawasaki Ninja 250s. Of course I think my WON SB25 is better than their systems as well. But for improved
Safety the streamlining rules have been changed since the 60's. Too much crosswind hitting the dustbin fairing in front of the wheel made the bikes go off the track. My tail goes to the edge of the rule but my front is still stock. I plan on proving it someday but playing with the Nitrous for now. Thanks again for your input.