My old Honda SL100


A HONDA SL100 MX Bike? Yea, RIGHT!

SL100_Homebrew

It was the early ‘70’s, I mean look at those lace up MX boots, real leather pants or ”Leathers” the bright orange Bell Star helmet (their first issue of a “full face helmet”) deer skin MX gloves, and those Hang Ten Florescent green top MX socks neatly cuffed over the top of your boots. Had to have a kidney belt too, your body was the majority of your suspension, and don’t forget your Jofa shoulder pad/chest protector just in case. Ready to race in the 80 degree heat for sure. Just like Roger DeCoster and Joel Robert in the Trans-AM races we went to at Puyallup Raceway Park

But really, I did race a Honda SL100. It was my third dirtbike if you count the 2.5 horsepower minibike and a Honda mini-trail 50 the neighborhood was terrorized with previous to this, but that’s a different story. We had loads of trails to ride back in the day, nothing like it is these days. My Father and I did a load of work to this thing after Mom was totally convinced that I was only going to race in the High School Motocross race ONE time ONLY! Then the lights and everything else were going back on, just like we bought that candy apple red SL100 Motosport! Sorry Mom, It didn’t happen and I can’t find the parts I took off anyway. I’m sure their here somewhere!

 I had a paper route to earn some money, selling off, horse trading and begging helped. Nothing seemed to happened fast, but now I see it really did. My Dad always seemed to come through with a couple more bucks or I did extra chores to help out with the rest. We were a typical middle class family with 4 kids. I’m pretty fortunate that my Dad had no problem taking on a new task, researching it, then doing as much as possible ourselves. A professional was called on for help when it was plainly clear we weren’t able to do something because we didn’t have the machinery, special tool or expertise to carry out the task. We had a great network of specialists as time went on. My Dad taught me when to get help before I fixed it to death, some of the time I listened! I learned one heck of a lot along the way from Dad and I still do. My parents are definitely from “the greatest generation” in America. I’m a very fortunate man.

SL100_Puyallup

At Puyallup International Raceway Park, site of the US Trans-Ama races in the 70’s

The bike evolved piece by piece. My Father and I went to work one task at a time as we raced it and collected the next hop up part. I got a pair of aluminum Akront rims with the big strong shoulder lip (that collected 7 lbs. mud on a wet day) from a kid at school off his Bultaco. Proper 18” rear and 21” front to replace the 17/19 stock steel units, we used SL125 spokes and learned to lace wheels! A fork brace was fitted to those thin stick 5” travel forks to keep things somewhat in line. Big, wide MX handlebars and a smaller SL70 fuel tank and seat were fitted up, Preston Petty plastic fenders replaced the ruby red steel ones. The swingarm was lengthened 1.5” at school in metal shop class. Betor shocks were fitted up, they puked fluid in no time so S&W’s were fitted.

SL100_Straddle Linea

The motor was being coaxed to life while the chassis evolved. Rocky, the parts manager down at the local Honda shop took interest (or was it pity?) and helped us out with parts discounts as we raced and worked on that little SL. The engine had a Yoshimura Racing 2 ring piston, their racing camshaft and their special knife edge lightened crankshaft. Way Cool Stuff! A Bassani reverse cone racing megaphone and a larger carburetor from a 305 Scrambler twin was fitted. The ports were worked over by Phil at MSI in Seattle, one of our go to guys at the time.

#13 wondering WTF was it that passed me?

 More (4 lbs.?) crankshaft weight was lost when we completely removed the stator and flywheel, no charging system whatsoever. It was called a “Total Loss” ignition system. A small 6 volt battery fed juice to the coil as needed. It lasted about 3-4 hours running time so you had to keep it on the trickle charger ready for action. We took a spare battery to the races “just in case”.

 With this done, we ditched the stock Dyno cover and made an aluminum 1/4” thick flat cover to replace it. We had the lower cam chain tensioner retainer built into it along with another aluminum ring to retain the stock covers rubber gasket. This was getting seriously “trick” for the day. Heck it looked like 1/3 of the lower engine was missing, just gone, how cool is that!

By now, this little thing was putting out some good power, and spinning up RPM’s fast! I was about the only person riding a 4 stroke at the MX or scrambles tracks at this time and place. I had been giving the 2 stroke riders serious hissy fits! I mean, can you imagine a pedestrian 4 stroke Honda trailbike beating a “real” 2 stroke MX’er? It happened on a regular basis and actually pissed off a few people! The 100 cc class was pretty popular at this time and I was consistently pulling off 1st, 2nd or 3rd overall.

Stator_cover
SL100_Holeshot

I think this picture shows it best. First corner holeshot at the OLD Straddle Line track in McCleary, WA, There was a very LONG starting straight, we’re talking better than 1/8 mile long. A stupid Honda 100 trailbike leads a bunch of Yamaha AT1’s, MX-B’s and Suzuki TM’s!

 Better yet, the starting gate was a stout steel square tube and diamond mesh construction that was operated by some huge air cylinders at each end. It went down fast and hard AND it fell FORWARD! This was imbedded in a wide concrete pad. When it was up, there was no way a motorcycle was going to push it down!

Eventually I learned the hot way to start. When the 30 sec. mark came, you got 2nd gear engaged and nosed up to the gate. When you felt comfortable doing this, you lean forward, light up the wick, dump the clutch and burn your tire until the gate dropped! Worked pretty good, but it sure hosed your tire!



LTR278.92

Telephone 360-871-2259 FAX 360-326-7282 E-mail les@lt-racing.com

6487 Knight Dr. SE  Port Orchard, WA 98367

Copyright 2009 LT Racing inc.

Marzocchi, WP, Sachs, Ohlins, KYB, Showa. servicing, tuning, revalving, forks, shocks,Honda,Kawasaki,Suzuki,Yamaha, TE, TC, TXC, WR. CR, CRF, YZ, KX, KXF, RM, RM-Z, EC, DE, MC, RR, RS