Dart 350 for Bonneville Land Speed Racing

[dr j]

I have now entered my newly imported Dart 350 in the Bonneville Land Speed Racing (LSR) event called BUB 2012. It is August 25-30 and is for motorcycles only. I spectated there last year and there was a Morini 350 that got a record. LSR has many different classes for competition and some are universal and others are venue-specific. I normally race a 1994 Honda RS125 chassis that I wedged a Honda CRF250R 4-stroke engine into. Up to now I have only raced with the East Coast Timing Association (ECTA) (website- ecta-lsr.com) which does a Standing Mile on pavement. Last year their track in Maxton closed but they found a new track in Ohio so the Ohio Mile was born this year. Maxton was 60 yr old concrete runway with patches and bumps. If you want to check out what Maxton was like watch my video on YouTube http://www.youtube.com/watch?v=i15VUkqo84I&feature=plcp. It has a start and a finish and a helmet cam view. My best speed with that bike was when running a UK Nitrous system from Wizards of NOS I got up to 131.8mph. I even got an interview in the Bonneville Racing News.
But as I said the classes are venue-specific and while the ECTA separates 2 strokes from 4 strokes the Bonneville groups do not. But because of the power of the Harley group they do have a Pushrod class which of course are all 4 strokes. That is how I found the Morini 3 1/2s. The Dart seemed like the same idea as what I did with my Honda combo. I also hope to take my 1954 Parilla 175 Sport in the Vintage 175 class.
There are many difficulties about Bonneville. 1. It is 2300 miles from me one-way! 2. Lots of safety regulations to meet for the tech inspection. 3. Not much oxygen in the air when it is hot and 4219 ft elevation so less power. 4. No spares out there
Many unbelievable things about Bonneville. It's like no other place on earth for Land Speed Racing. Very bizarre looking place. Amazing vehicles from all other the world converge there. Last year I saw bikes from Norway, Denmark, Australia, and UK.
I appreciate the help I have already gotten from this forum and I am joining the MRC. I will try to keep this thread updated with my build progress as I only have 9 weeks until I load the trailer. I will make separate threads for enlisting help on specifics. Any recommendations on better ways to do things are encouraged.
So here's this weekends things done list-
1. Made new tank straps
2. Made metal battery strap (safety requirement)
3. New chain on
4. New hand grips
5. Ordered vac gauges for carb balancing
6. Ordered new brake lines and banjos

[nickst4]

Jarl: best of luck: you certainly jump in at the deep end! I like the concept of making an opportunity of the push-rod design, rather than lamenting the absence of DOHC or desmodromics...

If you feel like sending your Parilla for a vacation over here, I can find a nice space for it!

Nick, UK

[dr j]

Thanks Nick. The Parilla is very happy to be joined by another Italian. But the Parilla is right now engine in pieces in a major upgrade to clutch, oil pump, cam, high comp piston, and cam gear drive conversion.

Today I finished the metal chainguard (1/8' aluminum) which fit nicely underneath the rear hugger though it has to extend beyond to go past the end of the rear sprocket. Something about broken chains hitting racers so rules are made.

I also replaced the fuel tank O-ring where it was leaking after cleaning the petcock.

Engine running better with slightly retarded timing. But without a Dart service manual I looked at my 3 1/2 manual and I was surprised to see nothing under the little upper left side cover where the tach drive is. That's where I expected the timing plate to be. Oh well, found it below the rotor. What a pain to get at those nuts especially the lower one.

Has anyone tried to swap the Dart ignition with a 3 1/2?

Still considering my paint scheme for the Dart.

[dr j]

Here's an update-
Dart 350 is now ready for the Land Speed Racing event this weekend at the Ohio Mile (ecta-lsr.com).
Over the last several weeks I have been hard at work. I did all the safety wiring and applied plastic number plates for running in the "naked class" (no fairings ahead of the rider, meaning none except for the front fender which is allowed). I was able to make a triangle lower mount for increasing the radius of the fender lowers to clear the front tire. No time to make a new fiberglass front half to account for the resulting gap, so duct tape will do for now. Made a plate for joining the lower front fairings together at the bottom. New brakes line on and bled. Head light taped. I also repaired the broken corner of the left rear fairing and the windscreen. Used fiberglass with aluminum plate insert for the bolthole. Came out well. No time for paint yet.

I will first run it in the Naked class, Modified Pushrod Gas 350cc. Then if all goes well I will put the fairings on and change to Modified Partial Streamlining 350cc and go again. It will be very hot 95F/35C so not much oxygen in the air so not sure how fast I will go. No rear sprockets to change to either so kind of limited. But will test the engine.
Here's a pic of the bike last night. And below that is the pic of my other image from first post that did not work. I will post the results next week. Thanks again to Paul Compton and his friend Roy Masters for getting me this bike.

[dr j]

Well I ran my Morini Dart 350 in the standing mile at Ohio Mile this past weekend. New track so all records were open at start of this yr. So I first ran it without fairings on a scorching hot, humid day with headwinds. Not ideal. But got it up to 88mph. Then put on the fairings and the next day was slightly cooler and no headwind but the best I could get was 92.88 mph. All 4 runs I did Sunday were in the low 90's.


Uploaded with ImageShack.us
I was using this as a trial run for Bonneville Salt Flats and to get to know the bike. Really helped. I had a lower fork bolt come loose. Also I dropped the bike when loading into the trailer and it cracked a fairing again as well as the left side handlebar mount. That is the silver Cagiva piece that mounts onto the top of the fork. Anyone have a spare I can buy quickly or know a source?
The engine sounded great and I want to thank Paul C for telling me to not be afraid to rev it out. On the first run I shifted at redline of 8500 and the engine would bog a little. Thereafter I shifted about 9500 and it liked that better without any sounds of floating valves.
Worst problem was the tuck position. I was comfortable but I can get my head down below the windscreen but then cannot see through the opaque front. So I need to mold a new one from fiberglass and then cut out a space for a lexan screen for view. Anyone already have the front fairing piece in FG molded already. I will have to do this in 2 weeks or so, but would prefer to not reinvent the wheel if someone has pieces already molded.
Bike was a blast to ride and started instantly everytime and even idled fine. All in all a successful first race meet for us.

So here's the list of things I am looking for-
1. Left side Cagiva handlbar silver piece
2. Windscreen molded in fiberglass
3. Rear sprockets- 35, 36, and 38T

[nickst4]

Good going, Jarl! I take it those were terminal velocities and not averages?!

Sorry, no stock of parts yet that would help you....

Nick, UK

[mantaray]

Very nice. Jarl

[morini_tom]

Thanks for the update Jarl, keep them coming!

I can help with the screen and clip on- have sent you an email.

Not aware of any off the shelf sprockets in those sizes. Paul might know a source though.

Tom

[smotorboy]

Hello Jarl, I'm here in Southern California preparing a 1985 Morini 350 K-2 for Bonneville as well. I will Not be ready to run this year at Bonneville but I am planing to have shake-down runs this fall at the El Mirage lake bed here in California.

We will be in Different Classes as I'm Supercharging my Morini . It has proven to be a very tricky and $$$ proposition so far, but I fully expect it to work out eventually.

If your Dart has the same style of rear sprocket as the K-2 Morini, I can give you a source that can supply you with the needed 35 tooth (or smaller) rear sprocket.

I wish you all the best and will follow your adventure closely as I will be in your footsteps .... I will be glad to help if I can ....

Questions: have you considered the P/P class as the Dart with it's OEM fairing would seem be a perfect choice ? and what cam do you have in your motor ?

Robert in California

[dr j]

Nick- Yes at Ohio Mile the only thing that matters is the last 132ft between the timing lights. Everything before that is, as they say, "interesting".

Tom- Thanks for the parts offers. You are sucked further into this project too! Emails have been exchanged.

Robert- I was born in North Hollywood, Calif and raised in Santa Barbara, and then grew up desert racing my 1971 Honda SL100. Where in SCal are you now? Thrilled to hear of your supercharging project. Sounds crazy. And great! Just my style. As for the P/PP 350, yes that is one of many reasons I chose the Dart as I can run the fairings in Production unlike the 3 1/2 models. But I have not gotten the stock rear hugger or muffler yet. so I chose to go with Modified this year. But I have contacted NLM re a rear hugger now. As for the cam I have done nothing to the engine internals yet. That will be a winter project since I just got all the pieces of the bike together last month. I will not supercharge mine but I do know Nitrous very well....... Good luck on the dirt in a few months. I think that's 1.3 miles to the timing lights. Keep us posted.

Does anyone know for sure if the Dart rear sprocket is the same as a 3 1/2? I assume they are not the same.

[smotorboy]

Very Good Dr J, Looks like you have things planned out well.

I'll research the sprockets that fit the DART as see what is what....

You have the "M" cam in your motor and I bet you'll see more top end power with an L-5 cam slipped into the motor....Others on this site are well versed on which cams do what and maybe they will chime in with their experiences.... I only have direct knowledge of the stock "M" cam in my Morini at this time. My motor makes peak power at 7900 rpm and falls off fast after that. Your shifting above 9K makes sense as the rpm drop put you right in the peak HP zone .

I'm in Orange Co, CA in the city of Costa Mesa, but I'm a transplant from Alabama....I retire last October and the Morini is my "One Day" project... I've wanted to go to Bonneville since high school and I intend to do it.

In the P/PP class, they will look at the exhaust outlet diameter very closely so try to document that the muffler is OEM and unmodified. I started to try the P/PP class first, but the K-2's fairing is so inferior to the Dart's fairing that I decided it would be futile in the long run....Hope you prove me right ....

Robert

[smotorboy]

Looks like your rear wheel and sprocket are from the Cagiva Freccia 125cc two stroke bikes...The C9, C10, and C12 models....

Chain drive was on the left side for the two-strokes and I bet that they just flipped the wheel/hub over for the right side Morini chain drive.

The Cagiva show using a 520 chain size and the Morini uses the 530 chain size ...Same pitch,,, different width chains....

Now for the tricky part....I have a catalog that shows the following for Cagiva sprockets ( this should be checked against the sprocket on the bike):

6 each 7.5mm bolt holes on a 125mm dia B.C. (bolt circle) with the I.D. of the sprocket hole 110mm...

I could not find an off the shelf 35 tooth sprocket. I would check with a couple of sprocket companies to see if they can (1) make you a custom sprocket or (2) supply you with a blank sprocket w/teeth that a local machine shop could modify to fit your hub....

The real issue is whether the mounting bolt pattern will allow a small enough sprocket for your gearing needs..

The fastest run in the USA that I've seen in the record books is 122 mph for any 350cc push-rod bike so I'd try to ultimately gear for 125mph at 8500/9000 rpm ..

Robert in California

[smotorboy]

Dr j, have you had any luck with sprockets yet ??? I have collected all my sprockets and have them on hand even though It is quite a ways off before I'll need the taller ones... Do you wish for me to contact my supplier for you?

Robert in California

[dr j]

Robert,
I was successful on the sprockets. Here is the key info-

1990 Morini Dart 350-

Inner Hub cutout ID- 110mm

6 bolt pattern, 8mm bolts

bolt circle diameter- 125mm

Chain size- 520

Note that it uses a narrower 520 chain than the 3 1/2 and also a 6 bolt pattern rather than a 5 bolt. I have used Rebel Gears in Tennessee for all my custom sprockets and they just told me what to measure. Then a quick email with info and a few days later the sprockets arrived!! I briefly mentioned my past success with my Honda 250 using their sprockets and they added me to their racing support program and gave me a huge discount on the sprocket order!! So now I have another sponsor sticker I need to add to the fairings. But they truly are great to deal with, and easy as just a husband/wife team.

I will update more later.

[smotorboy]

Great news Dr. J, I'll put Rebel Gears in my list of suppliers...They sound like good people to deal with...

Good luck at the Bub Trails and keep us posted day by day if you can....

Robert in California