Saturday, January 29, 2011

Supercharged Triumph Tiger Cub goes for the ton at Bonneville


Every year, motorcycle enthusiasts from around the world descend on the Bonneville Salt Flats, deep in the desert of Utah. Many are there to set new land speed records by building bigger and faster bikes than previously imagined. However, not all records are in the 200+ mph range. In the 50's the Triumph Tiger Cub held a land speed record, earning it the title king of the 200cc singles. Currently, Bonneville has many classes including the 250cc vintage class. Chuck Zeglin and Steve Moody set out to build a cub Salt Flat Racer that could push the limits of the former record. This proved to be no easy task. Getting a cub to break the 100mph mark is a feat in among it's self. They are almost there and at the rate they're going, they will probably far surpass that somewhere down the road. 

I have always been interested in Cubs. My dad left me his 1961 T20 bitsa. It's not terribly fast, but it's a blast to ride. I started thinking about building another Cub into a full blown race bake to see what it could do. Turns out, according to friends of my dads, he had this very same idea before he passed. Making small, simple, air cooled engines go faster has always interested me more than making bigger engines that have higher capabilities. When I learned about Chuck and Steves Cub project, I had to know more. I contacted chuck and he was more than happy to answer some questions:



First off, when did you get the idea to take a Tiger Cub to Bonneville? Had you raced there previously?

Well....... at an early age I took an interest in danger. Only 
joking! I first went to Bonneville in 2002 to help friends with a 
roadster that they were racing. In 2003 they let me make a run in the 
roadster and I was hooked. In 2004 I decided I wanted a Cub dirt bike 
just to have fun on. I found a Cub basket case and drug it home. 
Shortly after that my friend Wes at Four Aces and I were talking about 
Bonneville and thats when the light bulb went off. My dirt bike 
project then became a Bonneville racer project. I already liked Cubs 
so it seemed like a natural. The Cub was raced in 06 at Bonneville for 
the first time. Went 79 mph with a used bottom end a freshened up top 
end. Low performance cam. I was very happy with that.







Cub with standard Monobloc carb hit 79mph first time out




There are two of you (I believe) at Zeglin Moody Tiger Cubs. What are your roles?


"Team Cub" consist of me (Chuck Zeglin) and my good friend Steve 
Moody. I built the bike and ride it. Steve sponsers me and helps me 
campaign the bike. Steve is my crew, helps with the bike, starts me at 
the line (remote starter) chases me down the course and picks me up. I 
could not do it with out his help.


Chuck Zeglin







Steve Moody

What class does your machine fall under at Bonneville. What are some of the key parameters the bike must meet to qualify in that category?


The class I am currently in is APS-VBG which stands for Special 
Construction Partial Streamlining- Vintage Blown Fuel. 250 cc class. 
Special construction mainly deals with the frame. It allows a more 
radical machine. A custom frame, unlimited wheel base, two engines 
even. Seat height must be below top of rear tire. No restrictions on 
foot peg location. So my Cub is actually on the mild side for the 
frame class. I have a modified stock frame with a 4" stretched swing 
arm. Partial Streamlining allows you to have a fairing. Vintage Blown 
Fuel means a pre 1956 engine (head and case) With cubs though you can 
run an engine up to 1960 or so, any engine with the one piece crank 
case. Those are grandfathered in because they have no real advantages 
over the pre 1956 engine design. My current engine is 1958. Thats a 
good thing, availability of good engines is a lot better. You can run 
a Super or Turbo charger in the class. "Fuel" means you can run 
anything you want. Alcohol, nitro or even unapproved gas. In fact 
right now I'm just running unapproved gas. See in a "Gas" class you 
have to run their gas that they sell and then they seal your tank to 
make sure you don't tamper with it. So even if you're running their gas 
but you don't have your tank sealed that would be considered 
unapproved gas. I hope that makes sense. I will make the switch to 
alcohol and nitro soon.




How many years have you attended Bonneville and what were your results to date?


I have attended Bonneville every year since 2002 except for 2005. 
I have been racing the bike every year since 2006. First time out in 
2006, 200cc's, went 79 mph with a used bottom end a freshened up top 
end. Low performance cam. I was very happy with that. Best speed to 
date is 94.260 mph unblown with engine bored to 250cc's and the fairing.







Cub with painted fairing 






















Lets talk tech. Year of bike? Whats stock whats not? Bore? Stroke? Compression ratio? Cams? Valves? What kind of fuel? Max rpms you've run without problems? And obviously the blower - who did the machining and engineering on that number? I see what looks like a velocity stack sticking out the side. What type of carb are you running and how did you jet it. What were some of the challenges when fitting this supercharger? 


1958 frame, 1958 engine. Frame: swing arm extended 4", frame hoop 
around back of seat kicked up for tire clearance. Bolt in tube to 
replace stock gas tank. Ceriani forks. Sun rims, spool front hub. 
Barnes quick change rear sprocket arrangement. Owner built custom 
finned brake drum, seat, clip ons, oil and gas tanks. Engine: At first 
200cc's, used stock bottom end with fresh top end, .060 over 10.5 to 1 
piston, head ported with later bigger intake valve. Stock low 
performance cam. After that engine was bored from the stock 63mm to 
71mm with a Triumph 650 piston then used. That makes it 250cc's. 
Custom head with raised/relocated intake port. 1" Amal Standard carb 
with Amal "matchbox" remote float, 150 main jet. Big bore raised 
compression to 13.8 to 1. "R"code triumph cam now used. Alpha roller 
bearing big end. Later crank with bigger crank pin. 1 1/8th exhaust & 
1 5/16th intake valves. 35 degrees fixed timing. 7000 rpm. In this 
form went 94.260 mph. Crank shaft broke (crankpin) right after this. 
Hard miles I guess. To try a supercharger the engine was put back 
together with stock bore and stroke. A Chevrolet smog pump was first 
tried as a supercharger. I did all the engineering/fabrication. Others 
have had good success before with smog pump super chargers. Did not 
work out so well for me. Main problem for me was I was turning the 
pump the opposite direction from stock. This is OK but you have to 
completely reverse the vane seals inside the pump. I found out this 
information too late for Bonneville last year but tried what I had 
anyway. Pump self destructed on the first run. Was reading 9 pounds 
and feeling pretty good before it blew. Coasted down the track at 59 
mph. That was 2010. For 2011 I have rounded up a Aisin 300 roots style 
blower. This blower comes on a little Japanese 660cc inner city car 
not sold here. This should work out pretty well. A little big so I 
will only drive it about 45% crank speed. I will let you know how this 
goes.




Aisin blower mocked up

Fabbed up belt drive for blower

Right side of engine





























































How do the conditions at Bonneville effect the bikes performance. I've heard the salt can be loose and narrower tires help cut though the slop. Any other factors you've come up against?

As far as conditions not much seems to affect the bike at the 
speeds I'm traveling. After the 2006 season I did go to some proper 
Goodyear racing tires. They're 23.5 x 4.5 -18 front and rear. They are a 
slick tread motorcycle front runners currently used on drag bikes. I 
run 50 lbs in them. I'm sure they're a little faster having a smaller 
footprint and that they will safely take more air pressure. Fairing or 
not the bike is very stable.


Chuck Handeling the high altitude and loose surface with ease.


















You've mentioned that the fairing adds about 5mph. Any thought of going with a full shell or would that change the class completely?


Within the rules I can still add a front fender covering the top 
half of the tire. Also I'm allowed a small tail section behind me. 
Both will help and will be added at some point. In Partial 
Streamlining the riders complete body except for hands and forearms 
has to be visible from the side. A complete shell or body you actually 
sit inside is only legal in the full Streamliner class.



There's no big check for beating a record. What motivates you to keep going with what appears to be a costly and time consuming project? What is your goal? 100mph? after that will you go for a higher record? 


What mainly motivates me is the fact that it's so much damn fun. 
Also it's so rewarding when you try something new and your bike goes a 
little faster. It feels really good. Also the people you meet are the 
greatest. Everybody helps each other. A perfect stranger will go out 
of their way to help you. Our immediate goal is 100mph. I know of only 
three Cubs that have gone that fast, one being a full streamliner back 
in the late fifties. Dale Martin who is in the SCTA club the 
Sidewinders with me has gone 101mph on his Cub. And it was his father 
Bill Martin with his sons help that set a record of 139 mph in a full 
Streamliner in 1959. If I can do 100 I would like to build a totally 
new machine, still Cub powered, and go for higher speeds. Since I've 
gone almost 95 on gas with no blower I fell pretty good about hitting 
100 with the current machine.


Bill Martin and sons with their record setting sreamliner














Any other projects in the works or in the back of your mind? Any other bikes tickle your fancy? 


I have an E-Type Jaguar project in the garage that I want to get 
on the road. That will take some time. For racing I'm pretty stuck on 
Cubs. I have thought of a Cub road race bike also. Maybe down the 
road. For a road bike I would get a late model Triumph like a 
Thruxton. I like lots of bikes but I'm mostly a triumph guy. Ducati's 
are good too. For my next race bike I have thought of a duel engine 
Cub powered machine. Supercharged with high gear only and centrifugal 
kart type clutch.



http://www.zeglinmoodytigercubs.com

Chuck and Steve are raising funds for their project by selling Team Zeglin-Moody shirts. Support their cause! Click here to buy a shirt.




















I look forward to hearing Chuck and Steves results for 2011. I think hitting the magic ton will be no problem this time around. They'll be in a small group of people who have achieved that number. Once that's accomplished I see them going for something even faster. Plus with all the other T20 projects they have in their minds, it seems the skies the limit. I can't wait to see a dual engine cub take to the salt. How about you?

4 comments:

  1. I just came across this post a few days ago while researching the Triumph Cub. I believe you are using the same fairing that I started with for my BSA single. You must be racing with SCTA because I didn't see you at BUB. Did you race in 2011?

    The Assin supercharger is one I've considered and would be very interested in your results.

    Tom (AKA Koncretekid)

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  2. Tom, contact Chuck at http://www.zeglinmoodytigercubs.com and ask him these questions. I don't believe they run BUB but they'll be happy to answer your questions! Thanks for checking out the blog.
    matt

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  3. Hi Matt, great blog and brilliant article on the Cub! I am in the process of starting a magazine about Tiger Cubs and Terriers and wondered if you have any contact details for Chuck? I've been on his website but can't find an email addy. Hope you can help! Many thanks, Gorgeous Biker Chick, Scotland.

    ReplyDelete
    Replies
    1. Chucks email is jagwired@roadrunner.com. Is this going to be an online magazine or a print mag? I love cubs and have two of them. Would love to see what you're up to with this.

      Delete