52cc Predator Auger Powered X-Games FS20 BMX
- Thread starter 16v4nrbrgr
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16v4nrbrgr
Active Member
Just fired up the auger first try, this thing will run well at any angle of inclination with the pumper carb, I'm very impressed, it sounds nicer than the Morini, GASP!
16v4nrbrgr
Active Member
I used the auger to till up some roots and till up my beds in the yard, it's got good power although I think the break in mix I'm using is limiting the maximum power with the stock jetting as I could only get it to run best at 3/4 choke. It really needs 50:1, I think the Morini on the OCC will run better like that. I'm almost through this gallon of gas, some more rooting with the auger and a couple rides on the OCC and I'll use a regular mix ratio, as both of the motors have been run at the factory and broken in of sorts.
It's pretty amazing how low the emissions are on this thing, I can sniff the exhaust and its faint of crayons, cleaner than a car. There must be a catalyzer in the muffler. The stock muffler's pretty quiet, sounds good, would work fine for an economy BMX if cheap pipes weren't up on Ebay.
All I needed to get to adapt the pocket bike pipe was a 90 degree copper elbow from Home Depot for like $3 and it'll need a longer spring to hold the pipe to the flange. The slip joints work great, some silicone and a bit of wrap maybe if it leaks too much exhaust heat there and it'll be perfect.
The motor torques a lot in the direction opposing crankshaft movement, it's gonna torque the bike frame under acceleration, something to consider in design.
It's pretty amazing how low the emissions are on this thing, I can sniff the exhaust and its faint of crayons, cleaner than a car. There must be a catalyzer in the muffler. The stock muffler's pretty quiet, sounds good, would work fine for an economy BMX if cheap pipes weren't up on Ebay.
All I needed to get to adapt the pocket bike pipe was a 90 degree copper elbow from Home Depot for like $3 and it'll need a longer spring to hold the pipe to the flange. The slip joints work great, some silicone and a bit of wrap maybe if it leaks too much exhaust heat there and it'll be perfect.
The motor torques a lot in the direction opposing crankshaft movement, it's gonna torque the bike frame under acceleration, something to consider in design.
16v4nrbrgr
Active Member
The engine gearbox and pipe only weigh 17.6 lb total, add a lb or so for the front freewheel, not too bad considering its got some gas in it too. I think it has a cat, if so the stock exhaust will shed some weight removed, the pocket bike pipe will make this thing have top end.
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Buzzerbiker
New Member
That is gonna be some fun man! Your lean condition should improve with break in. However, The EPA, and CARB are pretty well entrenched into the lawn and garden market now, and these babies are really lean, and adjustability has gone from difficult to impossible in some cases. I have a couple small engine shops nearby that let me raid the bone yard for parts. I go looking for pre EPA carburators, $5 a pop. Worth it for the hard cases. Best of luck, can't wait to see more.
16v4nrbrgr
Active Member
Well, worst case scenario I'll grab a tiny drill bit and drill out the main jet, lol.
I'm gonna work on this today, the main plan is two clamps on the seat tube one on the bottom tube, and maybe a ring holding it to the bottom bracket via the crank axle housing threads.
It actually might be because of the 32:1 premix I used, and I'm not sure if its leaning out or choking up top, I think its choking because of the stock muffler with cat. It actually runs quite well until it seems airflow becomes restricted at full throttle or higher revs, because it doesn't hesitate or pop like its lean.
I think it's just the EPA muffler, this motor elsewhere is rated at 2.75 Hp and its rated at 1.5 by Predator, so I think tuning and the expansion chamber will make this motor great, well I know it will, these style engine are on every X1, X2, X6, push scooter etc. out there and there is tons of tuning info. I can't wait!
I'm gonna work on this today, the main plan is two clamps on the seat tube one on the bottom tube, and maybe a ring holding it to the bottom bracket via the crank axle housing threads.
It actually might be because of the 32:1 premix I used, and I'm not sure if its leaning out or choking up top, I think its choking because of the stock muffler with cat. It actually runs quite well until it seems airflow becomes restricted at full throttle or higher revs, because it doesn't hesitate or pop like its lean.
I think it's just the EPA muffler, this motor elsewhere is rated at 2.75 Hp and its rated at 1.5 by Predator, so I think tuning and the expansion chamber will make this motor great, well I know it will, these style engine are on every X1, X2, X6, push scooter etc. out there and there is tons of tuning info. I can't wait!
16v4nrbrgr
Active Member
16v4nrbrgr
Active Member
"German designed" supposedly and 33:1 so it makes gearing easy. I'm going to gear it for about 20 at first, and if it gets powerful after break in I'll gear it for 30 with an overdrive front sprocket on the transmission. Its easier to set up the clutch geared low too so its a good start.
16v4nrbrgr
Active Member
Today in between going and getting my motorcycle cert and riding my OCC I'll be working on this.
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16v4nrbrgr
Active Member
It'll need wide crank axle and shorter cranks for pedals so I'm going pegs. The right angle gearbox will clear a pedal sprocket with the box underneath the crankset so that's not a problem.
We'll see how far i get with it, right now I'm seeing what the most reasonable ideas are to put it together.
We'll see how far i get with it, right now I'm seeing what the most reasonable ideas are to put it together.
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16v4nrbrgr
Active Member
16v4nrbrgr
Active Member
Well, they way overtightened the rear axle hadware so I proceeded to break a vise (g-dang HF crapola) and hammer away on this damn thing and apply heat til the freewheel would unscrew since I couldn't remove the axle the proper way and take the freewheel tool to it. The cone nut on the right side is fused tight, this bike is gonna take weeks, who am I kidding thinking I'm gonna whip it into shape in a weekend?
16v4nrbrgr
Active Member
Well I hope there's not some ominous knowledge you have about these I don't know about, lol.
I think since my Motobike will have full fairings I'm going to steal the skid plate I bought for that project and put it on this to protect the engine and transmission.
I think since my Motobike will have full fairings I'm going to steal the skid plate I bought for that project and put it on this to protect the engine and transmission.