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[Frank]

2017 is the 50th anniversary at Winterport Dragway here in Maine, I've been racing up there for the past few years (won the bikes/sleds championship in 2014).  We raised money to resurface the track this year, including new starting line and shutdown.  Here's a video from my second race yesterday.  I rolled off at the end to make sure I didn't break out, a strategy that backfired in the next race!

[Alan Stewart]

Why don't you tell us about your bike?

[Frank]

Bike is a converted '76 Suzuki GT550.  I broke a connecting rod many years ago and built a commuter.  Sep-Ex motor, 72V of 100AH Thunderskys, it was a heavy but fun bike for tooling around.  Realizing that I wasn't getting any younger and wanted to drag race, I converted components to drag race spec starting over winter of 2013-14.  I used a 4" vintage slick, 4-brush ADC 6.7" motor and Z1K controller driven by 72S2P Lonestar Sleeper cells.  I quickly learned about chassis mods to facilitate hard launches.  I made a few more mods over winter of 2014-15 and raced all season in 2015, winning our local track Bikes/Sleds class (and NEDRA's points championship).  Same drivetrain except the motor was switched to a GE 7.5" motor.

The 2015-16 winter project was to back-half the bike, upgrade the controller (Z2K) and add battery (now 84S3P) and lighter wheels (Shinko Hookup rear tire).  The bike is now capable of serious speed.  I've run a best of 5.95/125 mph at 1300A and will improve on that this year.  Here's a pic:

[Starpower]

Interesting numbers compared to an ICE bike. You must get up to 125 mph in a heartbeat and it tops out there, is that correct? An ICE drag bike running that 1/4 mi. time would likely be over 200 mph. Maybe 20 years ago I had the pleasure to watch the "Kawashocky" make some impressive runs. Fun stuff, all the best with your future efforts!

[Frank]

I forgot to mention that it's a 1/8-mile track.  Actually, it pulls pretty strong on the top end; in this video I had rolled off the throttle as I was pretty sure I would win but I didn't want to "break out" i.e. run quicker than I declared.  DC motors will indeed top out depending on base speed.  With my current settings (no pun intended) I just hit motor voltage peak at the end of the run i.e. no controller cutback on motor amps.  At higher current settings it does start topping out but from what I've seen it more than makes up for it in better acceleration off the line.  The biggest issue up here is cold batteries.  The controller cuts back to prevent the pack from sagging too much and this is very noticeable.  After one or two passes the pack is warm enough.  It's only .2-.3 seconds difference but speed isn't as high.  Last weekend I had two runs with virtually identical ET's but 5 mph difference in speed.   

[Alan Stewart]

I was wondering about the track length when I first read 5.95. Is that kind of a time even possible on bike for the 1/4 mile?

Best of luck.

[Frank]

Top fuel can run the quarter in high 5's I think at well over 200 mph although many tracks are changing to 1000' in an effort to keep speeds down.  1/8-mile is gaining in popularity in many places (for lots of reasons).

[Frank]

I beat myself (red light) on this pass.  The guy in the other lane also redlit but his dial-in was a couple of tenths less than mine.  First mistake loses so I put myself on the trailer.  That's racing...  It was a 6.136/123 mph pass.