Can you take a closeup pic of the mount from above? I got an idea,but I need to know what the mount on the pipe looks like. And the diameter of the rack tube.
52cc Predator Auger Powered X-Games FS20 BMX
- Thread starter 16v4nrbrgr
- Start date
Thanks Maniac!
d_gizzle, the mount is basically based around a piece of split 1 1/2" tubing and two 1 1/2" exhaust clamps. The rack tube doesn't actually have a diameter, since it's D shaped. The mount you make depends a lot on your bike and the locations that should be held on it, and in which direction.
I managed to save myself a lot of work and used a Sturmey Archer cable holder to the rack mount on the seat, and a strong spring from the pipe to the mount. The muffler stays wedged in between the rack side bars and the center D tube above the tire, but can bounce around or shift if it stretches hot.
It's funny, I've reinvented the Yamahopper, lol. I'll have more pics tomorrow, it looks great all together, I'm stuck tonight staring at it in disbelief.
d_gizzle, the mount is basically based around a piece of split 1 1/2" tubing and two 1 1/2" exhaust clamps. The rack tube doesn't actually have a diameter, since it's D shaped. The mount you make depends a lot on your bike and the locations that should be held on it, and in which direction.
I managed to save myself a lot of work and used a Sturmey Archer cable holder to the rack mount on the seat, and a strong spring from the pipe to the mount. The muffler stays wedged in between the rack side bars and the center D tube above the tire, but can bounce around or shift if it stretches hot.
It's funny, I've reinvented the Yamahopper, lol. I'll have more pics tomorrow, it looks great all together, I'm stuck tonight staring at it in disbelief.
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First ride(s) were success! All the fundamentals worked fine. I just gotta focus on clutch tuning, then gearing if it doesn't spool up with clutch tuning, this thing has a wicked top end and I was stuck bogging it around at the max power it'll make with the auger clutch weight, set so people don't lose their arms, lol.
IIRC there are spots marked by the casting where you can drill holes through to mess with the stall speed, I gotta look up X1 clutch lightening and see what I can find. Rather than mess with more hook springs I might get the adjustable two shoe with coil springs for it.
The fender screws were falling out of the plastic so I took it off, zipties it is, like usual lol.
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You need 8 muffler clamps and a scooter deck cut in half,one for each side.
Btw,extremely nice. Now I really want one! +1! Freakin awesome!
Btw,extremely nice. Now I really want one! +1! Freakin awesome!
Muffler clamps? 
I'm gonna try and do without any decks, it fits the legal definition for a motorized scooter better than the CA DMV's example picture, lol. I did think about that, but there's no point. I have all the goped regs printed out from the DMV.CA.gov website and floorboards don't have to be flat. There is no definition, and pegs are more suitable for standing than boards.
I'm gonna try and do without any decks, it fits the legal definition for a motorized scooter better than the CA DMV's example picture, lol. I did think about that, but there's no point. I have all the goped regs printed out from the DMV.CA.gov website and floorboards don't have to be flat. There is no definition, and pegs are more suitable for standing than boards.
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I wasn't thinking about the legality of the boards,I was thinking about comfort and easy foot placement. Maybe put in a brake/light pedal,shifter pedal,or even a throttle pedal.
Naw, I want this to be my simple, easy, and LIGHTWEIGHT 
gas bike. I'm actually already enjoying how easy it is to work on! All you have to do to work on it upside down because of the pumper carb is pull the fuel bottle out of the holder and flip the bike on its bars and seat like a normal bicycle.
I was able to flip it, remove the engine, drill the clutch arms each in the two lightening spots though with a 1/4" drill, and put it all back together in less than an hour! Cam2 over at pocketbike planet drills out the 33cc clutches to 5/16, so I figured I'd start low and go from there, since it's harder to add material, and this is still a daily type of bike so I don't want it to slip too much. Right now its simply not getting up to the speed where the clutch and trans are locked 1:1.
By lightening the clutch the motor can make more power before its applied through the transmission. Hopefully its Goldilocks, if not, these two shoe clutches are the bottom rung, and cheap off eBay.
Another thing I can do to make the motor dramatically spool faster, but will limit top speed, so I don't want to just yet, is put an 18t on the transmission, which with this 14t rear will do about 20ish in my calculations. I know this motor should do 35+ with the right gearing so its just a matter of getting it to rev and put it through the clutch at a high enough rpm so it isn't all spun into dust like the safety settings right now. Ideally I want it so it will cruise very quietly at about 25 mph.
Oh yeah, the rear sprocket is just a RH threaded 14t fixed cog with a bottom lockring on top of it and 3 tack welds to the edge of the hub. Wheels greased with Mobil1 red moly, and the trans uses 200 mL of heavy gear oil, the break in oil had bronze bushing bits from the break-in, which is common with this trans. I replaced it with Mobil 1 75W-90 LS gear oil.
gas bike. I'm actually already enjoying how easy it is to work on! All you have to do to work on it upside down because of the pumper carb is pull the fuel bottle out of the holder and flip the bike on its bars and seat like a normal bicycle. I was able to flip it, remove the engine, drill the clutch arms each in the two lightening spots though with a 1/4" drill, and put it all back together in less than an hour! Cam2 over at pocketbike planet drills out the 33cc clutches to 5/16, so I figured I'd start low and go from there, since it's harder to add material, and this is still a daily type of bike so I don't want it to slip too much. Right now its simply not getting up to the speed where the clutch and trans are locked 1:1.
By lightening the clutch the motor can make more power before its applied through the transmission. Hopefully its Goldilocks, if not, these two shoe clutches are the bottom rung, and cheap off eBay.
Another thing I can do to make the motor dramatically spool faster, but will limit top speed, so I don't want to just yet, is put an 18t on the transmission, which with this 14t rear will do about 20ish in my calculations. I know this motor should do 35+ with the right gearing so its just a matter of getting it to rev and put it through the clutch at a high enough rpm so it isn't all spun into dust like the safety settings right now. Ideally I want it so it will cruise very quietly at about 25 mph.
Oh yeah, the rear sprocket is just a RH threaded 14t fixed cog with a bottom lockring on top of it and 3 tack welds to the edge of the hub. Wheels greased with Mobil1 red moly, and the trans uses 200 mL of heavy gear oil, the break in oil had bronze bushing bits from the break-in, which is common with this trans. I replaced it with Mobil 1 75W-90 LS gear oil.
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I pulled the spark plug, and this EPA pumper carb is crazy, the plug looks lean and clean, yet the thing runs like a champ and starts easy. I dunno if I should keep the jetting this way because its running well considering, and the gas mileage must be stellar!
I had an E3 performance plug identical in dimensions to the stock one so I put it in for giggles, they're supposed to make more power. I think at least they hit more consistently because they're like a Splitfire. Electrical charge accumulates on areas of small radius, hence why they spark better that way.
I had an E3 performance plug identical in dimensions to the stock one so I put it in for giggles, they're supposed to make more power. I think at least they hit more consistently because they're like a Splitfire. Electrical charge accumulates on areas of small radius, hence why they spark better that way.
I was also thinking about uncorking the air filter, but that's sometimes a path of diminishing returns and more unwanted intake noise. I have a cut down Uni filter and some bits to set it up, but with it running this lean its pointless at this point. I augered up a ton of roots and tilled beds, and rode around for about 15 minutes today and the plug looked like something out of my car with O2 sensor feedback. I guess the EPA really grabbed Predator's balls on these motors, wouldn't be surprised if I need to jet it and I should look into drilling it out or getting a different main.
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I'm going to put on better brake pads today and adjust them, the brakes were marginal at best yesterday.
Weighed the bike with my bathroom scale using the difference method, and it's 53 pounds fully wet with about a half liter tank of gas. With my skinny ass on it, it should be very fun today withe the higher rpm stall.
Weighed the bike with my bathroom scale using the difference method, and it's 53 pounds fully wet with about a half liter tank of gas. With my skinny ass on it, it should be very fun today withe the higher rpm stall.
All those mods worked great, I'm gonna do some riding and see if I can tell the mixture from the spark plug. I think I'm also gonna try a different gearing beacuse it will wail if I can get it going!
Yeah, its just spinning clutch and generating heat, I'm gonna put the 18t ACS Crossfire on the transmission and it should rev a lot freer, I know theres another double the revs I'm getting right now, it will be more of a monster but its just sitting and frying like my OCC did before low gearing it. I think this thing is balance at the factory because the top end is sweet, so I wanna reduce the load on the motor so it will get there.
I just ordered two more clutches to mess with since they are $10 each I could smell burning gear oil and there was a bit of smoke, the front main on the trans seeps a bit and when the clutch basket got really hot it smoked the oil momentarily. Hope the seal is OK, and the clutch is OK, I'm gonna put the 18t on itand see if I can get it to rev, it has not much bottom end at all, and it was slipping that away with the lightened clutch, guess thats why the lightened flywheels too. I'm not gonna go crazy with it, this is legal under 25 and it feels afe and stable and comfy at those speeds. Honestly, my other bikes are so ruckus and sport oriented they hurt me so this is a nice mellow change. If I can make it RIIPPPPPPP! I'll be happy with a lower top speed, and I need hill climbing, and with a 49cc with CC it means revs.
I could smell burning gear oil and there was a bit of smoke, the front main on the trans seeps a bit and when the clutch basket got really hot it smoked the oil momentarily. Hope the seal is OK, and the clutch is OK, I'm gonna put the 18t on itand see if I can get it to rev, it has not much bottom end at all, and it was slipping that away with the lightened clutch, guess thats why the lightened flywheels too. I'm not gonna go crazy with it, this is legal under 25 and it feels afe and stable and comfy at those speeds. Honestly, my other bikes are so ruckus and sport oriented they hurt me so this is a nice mellow change. If I can make it RIIPPPPPPP! I'll be happy with a lower top speed, and I need hill climbing, and with a 49cc with CC it means revs.
Wow, it was really difficult to get the freewheel unstuck from the 7/8 adapter, take it from me, pull the whole assembly off the trans, and stick it in a vice, heat it just below cooking the freewheel temp and wail on it with a crank axle and a big hammer, with pb blaster along with the anti seize on it already!
I'm completely spent after messing with that, phew!
I'm completely spent after messing with that, phew!
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PHEW! Got it back on, I hope the next ride works out well, that totally mind-effed me getting the other freewheel off. Guess it doesn't take much to really lock one of those suckers on there tight.
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Well, now it rips, but tit has legal goped top speed, lol. The drive chain causes a wowowow at high rpm which is annoying, but it rockhops pretty nicely and makes for good dirt road riding. I would like to maybe put pedals back on it eventually if I can afford to put some nice cranks and a sbp crank axle in there, and maybe a 3 speed rear derailleur for the pedal side. I'm not getting the type of speed I expected out of this motor, but I guess that's to be expected since I haven't richened it up or messed with any other tuning.
I stink like two stroke oil now lol
I stink like two stroke oil now lol
Here's a link to the PDF manual for the drill, I'm looking into maintenance and tuning info and theres a lot of good stuff in here, even a full blowup diagram
http://manuals.harborfreight.com/manuals/60000-60999/60622.PDF
http://manuals.harborfreight.com/manuals/60000-60999/60622.PDF
I found more information on the carb
http://www.goped-scooter-tuning.de/infos_eng/goped_tuning.html#walbro
Its a Walbro Wt668 I think, the picture for it mixes up the inlet and outlet fuel lines, but the original German picture has it right. Supposedly left is richer on the mid adjustment screw on top and the high on the side. The EPA modification might have blocked off adjustment so I'll see if I can get changes to make more power tomorrow.
http://www.goped-scooter-tuning.de/infos_eng/goped_tuning.html#walbro
Its a Walbro Wt668 I think, the picture for it mixes up the inlet and outlet fuel lines, but the original German picture has it right. Supposedly left is richer on the mid adjustment screw on top and the high on the side. The EPA modification might have blocked off adjustment so I'll see if I can get changes to make more power tomorrow.
I was planning on using this anyways...
"The best part of waking up... ...is old ladies in the neighborhood cupping their ears and complaining to each other!"
Yeah Lets quiet this down a bit, the stack is the end of a cut off grip from a grip shifter bike,Tell tale, naughty naughty, by the way, it rips now, lol!
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