I am thinking of a 6.5hp rear drive.

[CrazyDan]

It seems you have your gear ratio too low for the torque converter to even begin to adjust.

 

[bike4life]

It seems you have your gear ratio too low for the torque converter to even begin to adjust.

Tommorow i am gonna weld a 44t sprocket to 5/8 rod stock and will then take the train to harborfreight as my motorized bike will be under service. I will buy a 20" tire from harborfreight and take the train back home. Do you think a 44t sprocket and a 20" tire will work. The math says that will yeild around 40 some mph. The tq converter has a 10t output sprocket and is connected to a stock predator with max rpm of 3600.

 

[FNTPuck]

Tommorow i am gonna weld a 44t sprocket to 5/8 rod stock and will then take the train to harborfreight as my motorized bike will be under service. I will buy a 20" tire from harborfreight and take the train back home. Do you think a 44t sprocket and a 20" tire will work. The math says that will yeild around 40 some mph. The tq converter has a 10t output sprocket and is connected to a stock predator with max rpm of 3600.

In order to eliminate as many variables as you can, I would first just change the sprocket to see if it helps THEN change the tire. Always best to make one change at a time and document when troubleshooting, vs changing multiple things at once.

That being said, I am pretty confident it increases your speed by ~10mph or so on the same tiny wheel since you will have enough TQ to get the converter to its 1:1 setting. Then if you go to a 20" OD wheel, you will get your 40+mph.

Don't think anyway has gone that fast on a pusher, it doesn't sound fun or safe at all. Get a real helmet at least, not a construction hard hat.

 

[bike4life]

Thx FNTPUCK. Today, i almost finished fabricating the 44t sprocket so it would fit on a 5/8 shaft. I don't think the tolerances are too important.... But even if they were, i think i got it within pretty good standards for what i have.

See the sprocket has about a 2 ish whole in the center yet the shaft is 5/8. A lucky person with a metal lathe would just machine something with a 5/8 hole centered in a 2 inch ish ya know.... Well, decided to roll up some painters tape wrapped around the shaft so it would fit the sprocket, so it would be centered on the shaft. I'd say it worked pretty well. I am using a lock collar as a reference to make sure it doesn't get off alignment in terms of being perpendicular to the shaft, then weld it to the collar so its removable....

 

[bike4life]

I am curious why it wouldn't be safe or fun. I would think it would be just as safe or fun as a regular 2 stroke motorized bike or even a motorcycle.
You guys seem to run 2 strokes at 40mph, so why can't i do the same with my pusher, especially since it has a LOT more hp then a 66cc 2 stroke....
Bakaneo got his ebike to 60 even......

 

[CrazyDan]

I am curious why it wouldn't be safe or fun. I would think it would be just as safe or fun as a regular 2 stroke motorized bike or even a motorcycle.
You guys seem to run 2 strokes at 40mph, so why can't i do the same with my pusher, especially since it has a LOT more hp then a 66cc 2 stroke....
Bakaneo got his ebike to 60 even......

Because it will try to push your bike out of the way, causing you to jackknife. I don't understand how you can't seem to wrap your mind around this. I think you will ultimately troll yourself. Does your trailer have a brake even?

 

[bike4life]

Because it will try to push your bike out of the way, causing you to jackknife. I don't understand how you can't seem to wrap your mind around this. I think you will ultimately troll yourself. Does your trailer have a brake even?

The only way to figure something out is to test it. Maybe other ppl have built these things and ran them at a modest 40mph. Yes nearly anything can jackknife, but if I felt like it, I could weld restrictions to prevent the trailer from swaying more than an arbitrary number of degrees. But so far I’m not yet concerned. No, I haven’t welded a 3rd brake for the trailer yet as the engine seems to do a good job of braking. Idk about 2 strokes but going down hills, my engine would start to limit it a lot as currently it’s top speed is 20mph with the gearing issue. Remeber I weigh around 120 lbs and the trailer frame is maybe 100 lbs? So I’m not concerned yet....
Remeber that to every problem, there is a technical solution.

 

[Frogslayer]

I'm excited to see how fast it really can go. How did it feel even though it was slow?

 

[FNTPuck]

Thx FNTPUCK. Today, i almost finished fabricating the 44t sprocket so it would fit on a 5/8 shaft. I don't think the tolerances are too important.... But even if they were, i think i got it within pretty good standards for what i have.

See the sprocket has about a 2 ish whole in the center yet the shaft is 5/8. A lucky person with a metal lathe would just machine something with a 5/8 hole centered in a 2 inch ish ya know.... Well, decided to roll up some painters tape wrapped around the shaft so it would fit the sprocket, so it would be centered on the shaft. I'd say it worked pretty well. I am using a lock collar as a reference to make sure it doesn't get off alignment in terms of being perpendicular to the shaft, then weld it to the collar so its removable....

Dont run it like that lol.

You have a welder and I am assuming an angle grinder and drill- just cut a square section of ~1/8-1/4" sheet metal maybe 3x3", drill a 5/8" hole in the middle, notch a 1/4" square for a key, then weld that to the back of the sprocket (CENTERED WITH CALIPERS...not EYEBALLED). Then, on the front side weld the collar directly to the sprocket. Make the 2-3(depending on how many locks your collar has) divets on the axle for the locks on the collar to keep it from spinning, push a key through the back to further secure it and boom - a removable 5/8" axle sprocket with lock collar, with no damage to axle, won't break or move around, and won't cost you anything assuming you have a short section of 1/4" key bar. If not you can get them from many local hardware stores or tractor supplies for dirt cheap.

Much more secure than welding a tab to a floating sprocket thats likely going to snap when the TQ hits it. Needs to be secured directly to the axle with keys/collars.

 

[bike4life]

I'm excited to see how fast it really can go. How did it feel even though it was slow?

It was really cool. It felt kinda awesome.... kinda intangible but was happy it worked after all the time spent....