Indian Parts Europe - Supercharged 741 racer at Bonneville

Building Story here - Bonneville 2010 here

Salt Cracker goes to Bonneville 2011

Photo above by Bill Anderson. Photos on the left by Horst Rösler.

August 22, 2011 - Bonneville update: Lars and the supercharged 741 are now in the SCTA record books with an average speed of 119 Km/h (73.903 mph) in the 500 A-VBF class, after a best run at Speed Week of 160 Km/h (99.168 mph). There were some problems during the second run, but I hope they will be solved for the races at the BUB event at Bonneville starting next weekend.

When Lars gets home, I am going to twist his arm for him to pick up the building story where it left off back in 2009, but here is the long and short of it. Engine damage from its rough debut last year at Bonneville (blown head gaskets, wrong ignition timing, manifold leaks and, as it turned out, excessively high boost pressure, but still going 142 Km/h) amounted to no more than a burnt groove in the rear head where the gasket had failed, warped exhaust valves and flywheels having twisted a little on shaft tapers (they have now been Loctited). 741 engines are tough little buggers - in particular when put together right with good parts from IPE.

We finally got it on the dyno, where it turned out that boost was a lot higher than expected. With approximately 15 psi of boost it had around 40 rear wheel HP at 5000 rpm running on methanol. With a more moderate boost of around half that (blow-off valve partially open), around 30 HP. Blower gearing was changed to lower the boost before packing the bike, but not in time for more tests. A big concern was the CV carb float bowl running dry during tests, but also no time to test mods supposed to help with this. The head gasket problem appears to have been completely solved by switching to solid copper gaskets (I have these gaskets for 741, Sport Scout and Chief, by the way).

September 2, 2011 - Bonneville update: Supercharged 741 is now in the AMA record books, too, with an average speed of 157 Km/h (97.5 mph) over two runs at the BUB meet at Bonneville.

The record is in the 650 A-VBF class (A = special construction chassis. V = vintage; before 1957. B = supercharged. F = fuel other than gasoline/petrol; the engine runs on methanol).

The engine is 600cc - actually this is a standard IPE 600cc 741 engine, apart from bigger exhaust valves to help the supercharged gasses get out again, and apart from the blower stuff, of course.

The reason for the different engine size classes is that some organizing bodies (like SCTA) have a "discount" for side valve engines, letting them run in the next lower class - e.g. up to 650cc side valve engines run in the 500 class. Under other rules (like AMA) there is no such volume discount, so a 600cc engine, no matter where the valves are, runs in the 650 class; there is no 600 class.

Remember, when looking at the speeds here, that the combined temperature and altitude at Bonneville is the equivalent of an altitude of ~7250 feet, or 2200 meters, above sea level (according to the Speed Week timing slip above). This "thinner air" means that engines make less power here than they would at sea level - around 23% less, actually, if the equivalent density altitude above of ~7250 ft is correct, as standard air pressure at sea level is 14.7 psi, and air pressure at 7000 ft around 11.3 psi.

Record certificate! (photo by Bill Anderson)

There is a great article about the 2011 BUB Bonneville racing event on the fabulous Vintagent blog (photo from the article).

Salt Cracker goes to Bonneville 2010

Last updated September 5, 2010

Engine, Frame & Other Parts, Guidance, Sponsorship - and Long Distance Tech Support :-)

The Salt Cracker went to Bonneville for the 2010 Speed Week and BUB racing meets. Not really ready, but it was sort of now-or-never, so the plan was to get the bike to Bonneville and then take things from there. While not everything went perfectly with the untested bike, it got to race on the salt and now has an official AMA timing slip to prove it.

Salt Cracker.

All packed up. Ready or not.

While we wait for news from Bonneville, here is a short video of the first start up of the engine not so long ago back in Copenhagen -> August 17, 2010		Salt Cracker in the pits at Speed Week. Lars hopes to get the bike assembled today and through tech inspection. No internet on the salt, so updates when possible -> August 17, 2010
Then one morning you wake up, discovering that you are really there. In a van with an Indian in the back. August 19, 2010. First email update with photos made it through!	The Indian hits the salt after a 8000 Km journey. Getting the bike through customs was much less of a problem than had been feared.	Lars' pit host George had hand-hammered this fantasic aluminum Indian relief and brought it as a gift.	Salt Cracker pits, all supplied by George and the Tri-Mac Speedsters team. The nicest people on the planet!
Lars doing his "rookie run" on the Tri-Mac Speedsters #476B supercharged, intercooled 100 cc Yamaha two-stroke. There are classes for ANYTHING at Bonneville.	Ready for tech inspection. Even with all the rule reading and consultation back home, there were still things that had to be corrected before the bike could pass tech/safety inspection.	At tech inspection. Salt Cracker passed with flying colors, and the inspectors called it a work of art. Now to get ready for the first run... August 19, 2010.	There are still problems to be solved with the untried engine. It didn't get to run at Speed Week but BUB is just a week away!
Lars' (mobile!) workshop outside his motel room in Wendover - the little town next to Bonneville, and the only inhabited place for miles in any direction.	Main jobs on the list, to be done before BUB starts Saturday, is checking for leaks in the intake system and finding out exactly what current ignition timing is.	Improvised leak testing setup. "Cowboy tricks" rule when you have to work on your engine in the middle of a desert.	And leaks were found! One huge one, that must be the main reason the engine wouldn't run right + several smaller ones. Ignition timing was also way off.
Drew Gatewood of GEARS kindly brought this selection of pilot jets for the Keihin CV (Lars has a drill set for the main jets), so now there should be a good chance of getting in a run or two at BUB. August 28, 2010.	Finally! Salt Cracker on its first real test ride at BUB (and the first time Lars, or anyone, has actually ridden the bike). August 30, 2010 There are more details/additional info on the Update History page.	"I am an idiot", wrote Lars. Well... It turned out he had set the electronic ignition on the wrong cylinder, even after all our ignition talk. So, with ignition and air leaks fixed, it's RUNNING! If all goes well the first timed run will be today. Latest update: Water has cleared from the short course (it was flooded earlier today, and racing postponed), and bikes have started running. No news of the Salt Cracker yet, but stay tuned!	Salt Cracker is not the only Indian at BUB.
August 31, 2010. Weather is better today, and lots of bikes running on both courses. After a minor mishap that stopped the Salt Cracker's second test ride (see pic to the right), there should be a good chance to get in a timed run today, Tuesday.	Broken gear lever was quickly brazed up again, thanks to the many helpers. But it meant no second test run yesterday.	For BUB, Lars is sharing pits with Kurt from Reno, Nevada (originally Denmark) and his fabulous Vincent Black Lightning.	Lessons (so far) from Lars' Bonneville adventure: 1. Don't ever bring an unfinished and untested bike to Bonneville. It is a total waste of time. 2. Disregard the above. Bonneville is the best place on Earth to waste your time!
September 1, 2010. More problems Tuesday. The mounting threads in the bottom of the cast aluminum tank stripped, and Helicoils had to be found. Luckily the local auto store in Wendover had the right size, even if it was an odd metric one. After that was fixed, the gear lever broke again...	There is now a "Mk2" gear shift lever in place! :-) Click to watch video ->	But the engine runs good and strong now! So everything should be in place for a timed run today, Wednesday.	September 1, 2010 Update earlier today: Lars had a timed run this morning (Bonneville is 8 hours behind Europe), but I don't have the time for his run yet. Eye witness report: "It sounded good and looked strong".
September 1, 2010 Update earlier today: Got a text message from Lars: "Engine ran good and fast - blew a head gasket in the timed mile" (they time the middle mile of the 5 mile course). So not clear if there was an official time. I have later heard that it was the front gasket during this first run. I packed extra head gaskets in the spares kit I made up for him, so there should be enough for a few more runs, even if this problem persists.	2010 BUB course layout. Event Schedule/racing times. Last updated September 5, 2010	<- Map of this year's race courses, and event schedule. There is wind today, and they are not running the really fast bikes (streamliners etc), so the, normally 11 miles long, "International" course has been shortened to 5 miles, with both courses being used for the slower bikes (lines are long from the last days' weather delays). Lars ran on the shortened "International". After racing ends tonight, there is only half a day tomorrow...	September 1, 2010 Second run: Lars' official speed over the timed mile was 88.198 mph (141,91 km/h) - losing power from another blown gasket (the rear this time). Actually I think this is an OK speed, no matter what, for what is essentially an untested, undeveloped stock 741 engine with a blower bolted on and guesswork gearing (and keeping in mind Bonneville's altitude of 4300 ft/1300m with resulting thinner air), but let's see what it will do if he gets a perfect run.

September 1, 2010. Final update(?): It looks like racing is over for the Salt Cracker for this year. When Lars got the cylinder heads off the second time, the flame from the blown gasket had burnt a groove in one cylinder head. But, hey! He DID it! No matter how bleak things looked (and, believe me, they have looked pretty bleak at times), he kept the faith and soldiered on. Now we are much wiser as to what needs changing for next time. I think I can safely speak for Lars here, in sending a big and heartfelt THANKYOU! to all the wonderful, kind and generous people who believed in him and went out of their way to help him make his dream come true.

It's official!

Burnt gasket and head.

Tired but happy!

With a little help from... :-)

When Lars gets home, and has digested the huge number of impressions and inputs this trip must have given him, I hope he will find the strength to carry on the building story where circumstances put a halt to it, and keep up regular updates so his many - old and new - friends all over the world can follow the progress of his preparations for next time.

IPE is Proud to Sponsor Lars Nielsen's
"Salt Cracker" 741 Land Speed Racer!
Click here to follow the build-up story as it unfolds...
Last updated June 7, 2009

As I said above, I hope Lars will be able to write the rest of the building story soon.