Norton Ready for Bonneville Speed Trials

Having trouble accessing Putfile, so no pictures today, but I can do a status update.

The weather has been iffy. I managed two runs yesterday with good and bad results. The bad is that on the first run the engine quit running just before the timed mile, but it was just a lanyard kill switch that was intermittent, and we quickly shorted it out. I went out again, this time got partway through the timed mile at high speed when the bike began to weave. I slowed down and pulled off the course, so didn’t get a time. The good news is that the bike is a rocket ship. It ran like gangbusters, and the nitrous was a real thrill ride when I hit the button. According to the tachometer, I was running somewhere in the high 140s when I had to shut down. Was certainly less than that because of tire slippage, but still pretty hot stuff. We think it was probably somewhere around 142 mph. I was taking it pretty easy, but from the way it was pulling, it should be able to run over 150 mph with no problem. After some reflection. I'm pretty sure the weave was from the rear wheel losing traction and sliding from the extra torque hit from the nitrous. The salt was getting a bit soft in the timed mile. If I'd had some more experience with nitrous, I might have thought to just let up on the button and keep the throttle open. One of the guys here with lots of nitrous experience said traction with nitrous at high speed is a problem because the nitrous delivers it's full horsepower ht as soon as it comes on. There's no slow buildup of power, and the instant torque increase breaks the tire loose. That's what it felt like to me. He suggested modulating the nitrous by continuously tapping and releasing the button to feel for traction. I planned to give that a try today, but we got more rain last night, and the course was closed today. The weather is good, and the salt is expected to be good tomorrow, so we'll see what happens then.

Ken

Pictures from Tuesday.

This is what we drove through to get to the course. The little dots in the distance are cars and trucks in the pit area.



And a shot of comnoz pushing my bike in front of our pit area. Yes, that is water.



Ken

That is fantastic! Very jealous!

Ready to go


Paul & Sir Eddies machine


Paul's crew


various shots
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There was only one real Commando running this year. Tom Skemp came out from Wisconson and set a record at just over 100 mph in the 750 P-PC (Production Pushrod Classic) class. Classic is a fairly new category, that includes bikes prior to somewhere in the '80s. I don't have the exact date cutoff handy. Because it is a new category, it's fertile ground for setting new records. Tom just had the engine built with a fresh overbore, big valve head, cam, and compression, and we all think the bike has the ability to run a bit faster, but Tom ran into some problems with sorting out his shift points (not revving it high enough before shifting into top gear), and got sidelined by a leaking oil filter fitting and didn't get to try again. Like most of us, Tom plans to return next year to have at it again. This was his second time at Bonneville. He ran the same bike a few years ago right after he bought it, and caught the salt bug.





Ken

Cool! That's Rick Murray's F1 sidecar rig that I got to ride at Willow Springs in 2010. The ride of my life!

Well, we have been tested by the salt and found wanting, at least a little. I managed to get a clean run yesterday, but the engine was not running well, missing a lot above 4000 rpm. I managed to get up to speed and through the timed mile by using the nitrous early, but only managed a 120 mph average. Back in the pits we found the crankcases had cracked, so something is probably not right inside. It was also pretty slippery out there, and the bike was moving around a fair bit at the end.

After that, my racing partner Eric took to the course on the the Guzzi sidecar that he had brought along and finished putting together during our efforts, and said it scared him to death. He said it was moving around all over the course, just slipping and sliding. He managed a run at just over 100 mph, and said no way was he going out on it again. Might need a little development work! The bike had the same engine we had run in a sidecar streamliner last year at over 130 mph, so we were expecting much better times.

Still, we had a great time, as usual, and plan to return next year.

I expect Paul Bilton-Smith will relate his experiences in more detail, so I'll just summarize. He and his crew, with invaluable help and advice from Jim Comstock, worked into the wee hours every night trying to get the bike ready to run. They had issues with the custom ignition system and the carburetion, and had to replace a leaking head gasket, but finally got it almost there, when the time ran out. Paul is very committed to this, and his crew is a great bunch. They plan to return next year with the bike all sorted out. I'm sure it has the potential to raise the record much higher.

Thanks to Jim for his help with out bike also. He was part of our crew for most of the event, and he's the one that spotted the cracked crankcases. If he hadn't, I'd have probably tried another run with disastrous results. The cases were heavily reinforced with welded in bits, but had a lot of racing miles on them before I took the engine to Bonneville the first time. I think maybe the nitrous pushed it over the edge. I think we caught the crack soon enough that the cases can be repaired, but I may replace them with Maney cases if I keep using this engine on the salt.

I don't have any new pics, but I know Jim does. I'm sure he'll post some of them as soon as possible.

We're all off to the AHRMA races at Miller now, although we're not racing Nortons (Sound of Singles bikes). Just another excuse for good company and cheap beer.

Ken

Ugh, the wet conditions behaviors sounds like what I run into hydroplaning on MUD!!! Always an instant emergency crisis that is unpredictable, not like hydroplaning on water or dry Gravel which can be controlled somewhat like water skiing in flat tracker crossed up style. Wet mud skewing upset is the most predicable situation I know of to get hi sided instantly so I'd not risked it either with only a slight wind gust or eddie determining outcome. To try to stay upright and going straight It also takes exquisite throttle control of tire not to drag or spin it over 10%ish slip or game over. When we camped on beaches or Everglades muk we had a pan of water to step in before stepping into tent or trailer.

Appreciate the comment of comnoz's deep powers of observation alertness, as DynoDave impressed me with similar in past Peel's cases, like a magnitude level finer awareness - almost psychic viewing skill. There are a number of the mile long events on paved airport surfaces around the country that would be a safer proving ground.

Just discovered the smoking gun in the misfiring Norton. While sitting in the garage at Miller Motorsports for the AHRMA races, Eric looked over at the Norton and noticed the nitrous injector on his side looked kind of funny. He reached over to check it, and it came out of the opening for the injectors with no effort. The injector bodies on both sides had broken off at the threads. They were still in the adapter holes, so the bike still ran sort of ok when I hit the nitrous button, but was way lean from the air leak when the throttle was opened without the nitrous. Hopefully, the lean mixture didn't damage anything, but I'll find out when I tear the engine down.

I had to use steel braided hose for the nitrous and extra gas, instead of the nylon tubes most motorcycle kits use, because plastic lines for nitrous are not allowed at Bonneville. That puts a fairly heavy mass hanging on the injector bodies, which are only aluminum, and the vibration from the Norton was probably too much for the small threads. Back to the drawing board. I'll be looking for, or making steel injector bodies.

At least it's a relief to know what the cause was.

Ken

Great report and amazing pictures.

It's always good to find a small problem before it becomes a BIG problem, or a disaster.

You'll get 'em next time!

Picture time again. This is a shot of how the bike looked before we noticed the injector was broken. The injector looks like it is properly in place.



This is a picture of what it looked like when Eric reached over and lifted it out of the port! You can see the small tube that the nitrous passes through, but the main body of the injector is still in the manifold.



This shot shows the layout of the nitrous system hoses. They are quite short, and add a fair amount of mass to the injectors, which probably contributed to the failures. I'm planning to change the design for next year.



And this is where the cases are cracked. It's hard to see, but inside the red circle is a crack about half an inch long that extends from left to right.



Already planning for next year. I'm thinking of building a new chassis based on a Commando, with isos, for the big engines. Might help with the vibration. It would also give me a little longer wheelbase and a little more room on the bike for the rider to stretch out.

Ken

comnoz said:

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That can't be good for that truck!

How much work is it to get all of the salt off of your bikes after riding there?

Mark said:

comnoz said:

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That can't be good for that truck!

How much work is it to get all of the salt off of your bikes after riding there?

Click to expand...

I posted a picture of my bike after just one trip across the "lake" After 4 trips you could no longer tell there were fins on the cylinder or head -just a big lump of salt. After the 4th [and last] trip I spent 5 dollars at the car wash and 90% of it came off. After I got home I pulled the tank and seat and found another couple pounds of salt. I spent another hour with the pressure washer removing the salt from the hidden places so I could get a socket on the cylinder head bolts.
I still need to pull the wheels and make sure everything there is clean -it's time for new tires anyway before the next trip.

I will bet the ambulance people had a hell of a mess. They were making pretty good time across the lake. Jim