So wheni port matched the intake I made a gasket out of a aluminum pan but I wasn't so happy with it so I went to orileys and got a sheet of gasket material and also a new fuel filter. The sheet should last me forever and was only $6. I wanted a new filter since I just went through my first gallon and it's my only filter in the system and in sure there was crud in my tank.
micargi puma gts newbie build
- Thread starter Motakitty
- Start date
I took it on a ride to work today and noticed a couple things. The first is that I'm only getting about 23mph and it's bogging a bit after 3/4 throttle so a jet change is in order, might go with a .66. The other thing is that the aluminum hd exhaust gasket from sbp doesn't seem to seal. I did sand the muffler flange flat on a piece of glass but I guess I should've done the gasket too but just might make a gasket with the sheet I bought. "On a higher note nothing else broke and the bike rode very well, oh and it idles very well and accelerates good. It starts up fairly quickly too, I just need to tune the carb
I just ordered the drill bits and pin vise recommended in another thread so I can just drill my own jet. I know how to soldier from my remote control car hobby do i already have all the stuff to do it except the drill bits but now I will. I figure I'll just drill it a bit smaller then just try it until the bogging goes away. I'm not after full power I'm after a nice running motor that'll last. I'd like to cruise at about 28mph with a top speed of just over 30 which I don't think is too far from where I'm at right now but makes sense that I'm running rich since it was running fine on 16:1 but I just dropped to 32:1. Any advise you have please share I'm open to ideas.I do plan on getting an expansion chamber in the future as my stock muffler just lost one of its inner baffle plate thing, it literally just fell out when I took the cap off cause I heard something inside jiggling around.
Kity,
First of all, build yourself a nice expansion chamber that fits that long frame of yours!
2nd- Get yourself a nice air filter. with as little restriction as possible...
3rd. After you install both exhaust and intake, then begin tuning that carb.
The NT carb will be fine.
Get a micro drill bit set and determine your current main jet size with bits.....
Youll probably find that a LARGER jet size (as determined with the micro bits) will make that baby come alive!
My 26" mustang with a 36 t sprocket and 66cc port matched only stock engine is pushing 35mph after 90 miles of break in at 28 to 1 fuel. Its getting faster as it breaks in!
First of all, build yourself a nice expansion chamber that fits that long frame of yours!
2nd- Get yourself a nice air filter. with as little restriction as possible...
3rd. After you install both exhaust and intake, then begin tuning that carb.
The NT carb will be fine.
Get a micro drill bit set and determine your current main jet size with bits.....
Youll probably find that a LARGER jet size (as determined with the micro bits) will make that baby come alive!
My 26" mustang with a 36 t sprocket and 66cc port matched only stock engine is pushing 35mph after 90 miles of break in at 28 to 1 fuel. Its getting faster as it breaks in!
Did you ever install a front brake?
Even with a decent brake up front....
21MPH is against the law around here.
25mph is silly.
30mph is dangerous......
35mph is stupid and mental....
40 mph is INSANE!
P.S. Not trying to sell you anything but I do have a several used, custom built Micargi expansion chambers left over from my numerous experimentations, or I can help build you a custom system!
Even with a decent brake up front....
21MPH is against the law around here.
25mph is silly.
30mph is dangerous......
35mph is stupid and mental....
40 mph is INSANE!
P.S. Not trying to sell you anything but I do have a several used, custom built Micargi expansion chambers left over from my numerous experimentations, or I can help build you a custom system!
I do have a nice air filter. I was under the assumption that since I have bogging after 3/4 throttle that it's running rich so a smaller jet is in order. I haven't installed a front brake yet I've been keeping it around 22mph for the most part. I'll only do more where it's a straight road with no cross traffic but I know I need the brake. I'm trying to sell some of my rc stuff to get some money for the brakes. I have about 80 miles on my motor so far
23mph.....Some thing is not correct.... I would expect 28mph to 30mph .
I would focus on a different exhaust, and only then begin to play with carb jets.
Once your satisfied with your current exhaust, then I would definitely experiment with jetting.
If you go through the trouble and time of jetting, and then latter change your exhaust, you will have to do the jetting again!
You may be too rich with stock exhaust.
Get yourself a micro drill bit set from widget.com, and a soldering iron.
I think the bit set is $5 and will be worth it.
Remove current jet, and use the bit set to determine where your at for a starting point.
Then solder it shut with as little solder as possible.
Then hand drill it one size smaller, reinstall, and test ride.
Test ride should be long enough to get the engine good and warm. 4 or 5 miles or more. After 4 or 5 miles. see if your top speed increases, and do a plug "chop" right before you end your test ride.
Let engine cool, remove plug, and examine.
If the plug looks rich, and your speed increased, you know your heading in the right direction!
Continue process until plug chop produces a light brown color...(Light brown like a paper bag from the grocery store).
Once you get a light brown color, I would go backwards ,1 size larger (richer) just to play it safe.
Its tedious, but it will pay off!
But remember, if you change the intake or exhaust, youll have to start the process over again!
I would focus on a different exhaust, and only then begin to play with carb jets.
Once your satisfied with your current exhaust, then I would definitely experiment with jetting.
If you go through the trouble and time of jetting, and then latter change your exhaust, you will have to do the jetting again!
You may be too rich with stock exhaust.
Get yourself a micro drill bit set from widget.com, and a soldering iron.
I think the bit set is $5 and will be worth it.
Remove current jet, and use the bit set to determine where your at for a starting point.
Then solder it shut with as little solder as possible.
Then hand drill it one size smaller, reinstall, and test ride.
Test ride should be long enough to get the engine good and warm. 4 or 5 miles or more. After 4 or 5 miles. see if your top speed increases, and do a plug "chop" right before you end your test ride.
Let engine cool, remove plug, and examine.
If the plug looks rich, and your speed increased, you know your heading in the right direction!
Continue process until plug chop produces a light brown color...(Light brown like a paper bag from the grocery store).
Once you get a light brown color, I would go backwards ,1 size larger (richer) just to play it safe.
Its tedious, but it will pay off!
But remember, if you change the intake or exhaust, youll have to start the process over again!
I was getting 28-30mph on 16:1 but I just dropped to 32:1 it has more power down low but higher it bogs. I don't plan on getting a exhaust anytime soon and don't mind doing the jetting, I ordered the bits and pin vise last night and I already have a good iron. Pm me with some prices on the mufflers. The next purchase is gonna be brakes for sure.
I just realized that I have my stock nt carb too(I have a nt speed carb on right now) so I can rob that jet and have two. I also realize that I could probably just add more oil to my gas mix but I did like the extra torque down low so that's why I want to keep the mix I have and just tweak the carb
32 to 1 is probably o.k.
Although it seems odd to me that you were hitting higher speeds with 16 to 1.
If I were you, I would stick with the jet that you currently are using...Then wait until the micro bits arrive....Then use the bits to determine exactly what size jet you currently have.... Then solder and re-drill one size smaller and test.
Although it seems odd to me that you were hitting higher speeds with 16 to 1.
If I were you, I would stick with the jet that you currently are using...Then wait until the micro bits arrive....Then use the bits to determine exactly what size jet you currently have.... Then solder and re-drill one size smaller and test.
Thanks that's my plan. I'll even check the other jet too just to see what size it is. I was expecting to see slightly higher speed too but I know after I rejet it'll be stronger cause it was stronger down low. From idle to 3/4 throttle it got up there quick and that's with a 36t sprocket and I weigh about 190 do that's not bad. I like working on things so rejetting isn't a big deal.
I've got this exact bike. I built it about a year ago. I fabricated my own front engine mount and I drew the rear sprocket and wheel spokes in autocad to figure out where to drill new holes for the stock kit sprocket. i posted the drawing here on the forum. I also did the same trick that you did running the pedal chain under a pulley to clear the bottom of the motor. I've got a couple of questions..
1 - where did you buy your front engine mount from ?
2 - what did you use for the rear sprocket ? did you buy one that fit the wheel ? from where ?
thanks. p.s. I LOVE my stretch.. it's awesome.
1 - where did you buy your front engine mount from ?
2 - what did you use for the rear sprocket ? did you buy one that fit the wheel ? from where ?
thanks. p.s. I LOVE my stretch.. it's awesome.
1. It's a universal cnc mount I don't remember where I bought it from but I do think I linked it somewhere in this thread, or just Google it it should pop up. I also had to add a strip of metal between the mount and frame cause the id and od weren't quite the same.
2 the rear sprocket is a manic hub adapter. They make em for micargi bikes. I had to bend some spokes out of the way to get it to fit though.
I want to redo the bike side tensioner though. It works but I want it cleaner.
2 the rear sprocket is a manic hub adapter. They make em for micargi bikes. I had to bend some spokes out of the way to get it to fit though.
I want to redo the bike side tensioner though. It works but I want it cleaner.
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yep - just saw your pictures of the bent spokes. if you build another one, do what i did - grab my drawing, bolt the sprocket, rubber, and split rings all together, then use my pattern to drill new holes. it fits perfectly and no need to bend spokes. Also, you can go to a thinner chain ! i got mine from Lynn at custommotoredbikes and it gave me plenty of clearance between the frame and tire. I'm still running the 2.125 tires with plenty of room.
I'll check out that site but I'm pretty happy with everything right now but ya would like to go to a wider tire when the time comes
I was just looking at that site at adding a disc brake to the front. The 415 chain wouldn't go around my rear sprocket though that's why I went with the 41 which fits the sprocket like a glove.
yeah - I've got disc brakes on my front wheel. Lynn has the setup but I recently bought a setup from bicycledesigner.com I think it was a better price and they had everything I needed for a front disk brake setup for a springer front end. however, Lynn has the "doughnut" adapter that you can use on the micargi wheel where you drill holes to bolt on a disc to the front wheel. i also use the 'alongha' brand caliper with the special shims to align the caliper correctly to the disk. it works great. check it out....
http://www.custommotoredbicycles.com/disc_brakes_rotors_26_inch_wheels_conversion_brackets
http://www.custommotoredbicycles.com/disc_brakes_rotors_26_inch_wheels_conversion_brackets
That's the setup I was looking at.with the doughnut the whole disc brake setup was like $100 so not bad. I'll probably get that when I can afford it.
I checked my plug and it was charcoal black so I know it's running rich but I'd rather it run rich than lean. My drill bits should be here on Monday maybe tomorrow. I also replaced my spark plug boot with a better one I had lying around. My stock one has a crack on the top. I replaced my exhaust gasket too. The aluminum one was leaking like there want one even there. I'm gonna ride it tomorrow so I'll see if the exhaust leaks.