Well ok…..so it’s not really a “Dyno”…..it’s just a bunch of old Go-Kart parts cobbled together…

…...but it’s fun to play with, there’s an ever present element of danger to it, and it has actually proven to be a very useful device.
Now raise your hand if you’ve ever tried to adjust the main jet on a carb while riding at top speed…either burning your hand or nearly wrecking yourself in the process….

hmy: …I’ve done it many times over the years, sometime even riding “cross armed” …throttling with my left while I reach down with my right….a bit hair raising to say the least.
So I’ve had this idea kicking around in my head for probably a year. We started stashing the parts we collected under a bench in the garage…..me and the kid decided to dig the stuff out and put it together just prior to Windber…..
Essentially it’s just a set of rollers….to be specific they are made from a 50mm kart axle and “cassette” bearings that I dug out of the trash at the local track. You just need to watch the guys with a lot of money…they don’t bother to straighten an axle or re-use the bearings…they just replace everything. :shifty:
The frame is just some heavy (3/16”) C-channel . We decided to bolt it all together so it would be serviceable in case the bearings go bad. We cut two 12” long rollers out of the remaining straight portion of the axles and installed the bearings on each end.
There are 4 sleeves that act as spacers between the sections of C-Channel. These were made from an old discarded nerf bar we had..(this is why I never throw anything away :wink

..
4 Lengths of ½-13 threaded rod pass through the tubes and the channel and 4 nuts and lock washers hold it all together nice and rigid.
The bearings are located and clamped using carriage bolts and small pieces of tubing.
So what is it good for…?? Well besides annoying the neighbors we don’t really have any room to ride where we live….we have to load the bikes and take them somewhere everytime we want to test one. Now we just chock the front wheel…set it up on the rollers and let it rip. You can exert a fair amout of load on the bike just by bearing all your weight down. If I get time I may even incorporate a little band brake on the rollers to provide increased loads.
Here it is in action.....
Mini Bike Dyno - YouTube
In the short time we've had it, it has proven to be invaluable for testing carbs, clutches, chain alignment, TAV operation, etc….The whole thing is only a little more than a foot square and stores away or travels easily…..
I only wish I had taken a video of
Hent on this thing at Windber. He had that obnoxiously loud Bonanza wound up on this thing where I thought the bottom end was going to fly out of it :lol: It was a real crowd pleaser……!!
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