So I found out that my speed carb has a #70 bit jet and my stock carb has a #71 bit jet so I'm gonna redrill to a 72 or 73 as I don't think going down just one size will help and I remember when I had that carb on it did the same thing.
micargi puma gts newbie build
- Thread starter Motakitty
- Start date
So I took it for another ride today and it seems like the 73 jet is to lean just a little bit. I'm going to try to go to a 72 jet or drill bit size actually and see how that goes since it still bogged out on the top end the rest of it seemed ok coming up from from idle to three quarter throttle. the top speed of it still says the same out of about 23 miles an hour
So on my way home today it wasn't running good. It was bogging all over the place, it was also running hot too. As strange as it sounds it was running great with the 16:1 do I might go back to that as it's in the mid 80's and I was getting the speeds I was after.I'll go back to the stock jet size too or maybe a size smaller than stock
So after sleeping on what I'm gonna do, I decided since I dropped jet size and now it isn't running better it's running worse I'm gonna go up a jet size and see how it's running. I'm also gonna get a ngk plug to replace my e3 plug since everyone recommend the ngk plug. Then if it still isn't running good I'll go up another jet size before I resort back to changing the oil ratio.
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I pulled my plug and it was a light brown color so I know I'm getting close. I opened the jet to a 72 drill bit size so I'll see how that is. My head bolts were a little loose too so I snugged those up( yes I plan on replacing the acorn head nuts).
Well I took it to work today and it ran a ton better no bogging except for at wot. Top speed was 24mph so I'm going in the right direction.I'll probably go to a 71 jet and see how that goes which would be the next size smaller than my stock one but whatever works. Let me know if that sounds right or maybe I'm not thinking of something else. Still running the e3 too.
Sorry for the many updates but I'm trying to be thorough. Ride home today went well it was 4 stroking a bit at idle which I didn't mind. It had a bunch of power from idle to wot but did bog or 4 stroke at wot a few times when I was at 3/4 throttle I would give it full throttle and it felt like there was power there but it would bog and slow down so I'll try the 71 jet and see what happens. My temp was allot better though.
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Today I went and got a couple ngk b7hs plus so I'll gap it at .025 and see how it runs before I mess with the jet again.
So this is what my e3 plug looked like. I installed the ngk so I'll see how it runs before I make another jet change.
Rode it this morning and the spark plug didn't help my issue. From idle to 3/4 throttle it runs great but at wot it still Boggs, it feels like it wants to go but it chokes. I'm topping out at 24mph. I might play with the oil ratio since it did seen to like the rich 16:1 I might go to like 30:1 or somewhere around 24:1.
So I was reading through threads about the bogging I'm having and I had a thought. Maybe since I lowered my oil ratio and maybe the motor isn't broken in completely that the rings aren't sealing completely causing loss of compression at high rpm. I figure if I was getting good power and the motor was running great at 16:1 then it's fine for now and I don't think the extra oil is bad for it right? Oh I'm using royal purple oil.
Maybe your fuel delivery is clogged. Take that petcock apart and see if anything is stopping the flow. Try removing the internals completely, seal it somehow, and see how it runs. I had the exact same problem, bogging at high RPM and basically modified it- removed all and epoxied in a plastic lawnmower shutoff valve from OSH.
I'll check that for sure. Now that I think of it when I drained the fuel bowl when I changed the jet a bunch of crud came out. I completely forgot about that. Maybe I'll replace the shut off valve and swap out the one on the speed carb with a 90° fitting. A clogged fuel system kinda makes sense but I'll check into it.
I started ordering parts for a front disc brake. I ordered a caliper bracket, disc adapter for my wheel and a disc. I just need the caliper, cable and lever. I don't really like the look of the disc brake in front but I know that it's the best kind of brake and I know I need it so I'll take form over function.
So I was reading through my manual and it says to break in at 16:1 for first 2 tanks and then go to 20:1 after that. I swore I read go to 32:1 so I'll probably go to 20:1 and then jet accordingly.
Got my caliper and cable ordered too. The only thing left is the lever but I think I have one here or I can steal one of my brother. I still would like to put a caliper brake in the rear ava have the coaster brake as last resort or just remove it all together so I can free spin the pedals. I don't really plan on riding my bike to much this week as I have to work later so I'll go through my fuel lines/shut off valve. I'm thinking I should add a fuel filter before my shut off valve too.
Today I pulled my plug and it the electrode was a light tan color at the tip and darker at the bend. The porcelain was the same light tan color. I checked my shut off valve for crud but it was clean, my filter wasn't clogged either and the shut off valve at the speed carb was clear too so it's not a fuel delivery problem. I think the motor just doesn't like the drastic drop in oil ratio so I'm gonna up that and go from there.
I replaced my shut off valve and I switched to 20:1 oil ratio so I'll see how it likes that. I got most of my brake stuff in i ordered from custom motor bicycling and I was sent the wrong disc brake bracket but they're sending me the right one and letting me keep the one for a straight fork although I don't think I'm gonna use it. Quick customer service though I highly recommend them. I'm still waiting for my caliper(from China) and my cable but that's fine as I don't have allot of time to work on it anyways but it'll get done.
Here's the disc installed. I had to drill through the wheel and it all bolted on. I used cut pieces of zip ties to center the adapter on the hub and checked it with string and it's all nice and centered. Very easy install though.
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