New project - 1980 Yamaha Champ

[typeone]

it cleaned up a little more after this vid but i want to drain the current gas, change oil, and set plug gap before i take it out for a full rip at lunch.

[xrocket21]

can this be plated!??!?!

[typeone]

can this be plated!??!?!

yup! once it's totally sorted i'd like to reg it, kinda similar to the older OHV plate in MA, $40 every 2 years. (the rule is 50cc / 25-30mph max though, *wink)

i still have the blinkers, plate mount, ordered a horn, etc. one tricky thing is it's a 6V system and i'd like to upgrade the lighting first. i have some nice 6V products bookmarked for when i get to that stage. (maybe in another 10 years?! heh)

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unrelated to the above, i also bought what i thought was a longer drive shaft and housing to stretch the rear but ends up it's the same length. bummer. would like to try to squeeze a fatter rear on.

[xrocket21]

Badass! That thing looks so fun

[typeone]

nope. seized again. don't think these CHYNA parts are working for me. i had the 90 main in and didn't romp on it. the 97.5 was too blubbery, will try a 95 since i was able to free the piston but know it's gotta be crap in there. also dropped needle clip to richen the mid, 5th position too rich, 4th not too bad. was in the 3rd.

thinking it might make more sense at this point to go with a Mikuni + Malossi kit instead.

[xrocket21]

Dang, that's tough luck

[typeone]

starting to wonder if i've got an air leak somewhere, will need to test ... should prob do crank seals before burning up another BB kit as well, seems the old Yamaha's always need new seals. i've also been reading about QT50 peeps using double gaskets for cylinder and head. not sure what that's about yet. also some noise about a very slow, 7 heat cycle break in.

bummed this will prob become a complete teardown this winter but at this point, might as well do it right. the good thing is i'm finding very similar scenarios after install of the eBay 60cc kits.

[typeone]

haven't torn the top end down yet but bike is running again. did another heat cycle but may swap rings just to see if they seal, pretty sure i can clean up what i have between the two kits. no word from seller on this second seizure but i'm starting to read plenty of comments on these cheap kits being shit. tolerances all over the place. makes sense.

needle on 4th clip, 95 main, AS 1-3/4 out, 3 stage cooler plug NGK 4>7 ... idles great, revs OK, little boggy accelerating into 2nd gear slowly but i'm going to try to do 5 more heat cycles on the stand to see if i can get her to run fairly normal. don't really care about locking it up again but hope it doesn't. 3rd seize was on a corner, pucker moment.

snugged head bolts, checked for air leaks around intake, re-piped a vacuum blockoff on intake, and i'll probably constrict the UNI filter a bit.

[Jlugo]

haven't torn the top end down yet but bike is running again. did another heat cycle but may swap rings just to see if they seal, pretty sure i can clean up what i have between the two kits. no word from seller on this second seizure but i'm starting to read plenty of comments on these cheap kits being shit. tolerances all over the place. makes sense.

needle on 4th clip, 95 main, AS 1-3/4 out, 3 stage cooler plug NGK 4>7 ... idles great, revs OK, little boggy accelerating into 2nd gear slowly but i'm going to try to do 5 more heat cycles on the stand to see if i can get her to run fairly normal. don't really care about locking it up again but hope it doesn't. 3rd seize was on a corner, pucker moment.

snugged head bolts, checked for air leaks around intake, re-piped a vacuum blockoff on intake, and i'll probably constrict the UNI filter a bit.

Hello, I was wondering if you could let me know what carb you ended up switching to. I've cleaned out the original my Champ came with but the previous owner had cut hoses before I got it, so I'm thinking my best bet would be switching since the connector that mixes the oil and fuel together is gone would be the easier option.

[typeone]

Hello, I was wondering if you could let me know what carb you ended up switching to. I've cleaned out the original my Champ came with but the previous owner had cut hoses before I got it, so I'm thinking my best bet would be switching since the connector that mixes the oil and fuel together is gone would be the easier option.

hey, sure. are you still running the original petcock? i switched to a basic on/off petcock and blocked any vacuum lines that were connected to the original.

after removing the oil pump, i ran the stock carb for a while with the bi-metal valve in the head and hoses intact. worked fine but the gaskets were getting pretty brittle in the orig carb. next i switched to a PW50 clone carb, been running that for a while although i hate knock-off carbs so i have a genuine PW50 Mikuni sitting on my desk here. that will go on this summer with some additional jetting tweaks. i'll need to read back what i was testing out but i know i want to shim the needle and try a different main.

[Jlugo]

I was thinking of picking up a pw50 carb, but I also have to look at other things the bike is missing. I'm rather new at fiddling with bikes.

[typeone]

I was thinking of picking up a pw50 carb, but I also have to look at other things the bike is missing. I'm rather new at fiddling with bikes.

yeah, you can grab one cheap, the only annoying thing will be the remote choke cable. the PW50 has the lever mounted behind the front number plate so you can either mount similar or shorten the cable, which is my plan.

have you visited Moped Army yet? some old threads there that might help understand the bike as they're pretty rare. QT50 info can be helpful for motor related stuff as well.

[Jlugo]

I've been looking. I've read two different post on moped army and here. I've also looked for videos on youtube, but people don't really explain or show much of the work, so I've been going through trial and error right now. I'm looking to change the carb, breaks, and the speedometer/ ignition switch were broken by the previous owner. I can tell it turns over but i'm not getting spark. I'm assuming thats because the top head needs replaced since i've tried a new sparkplug. This thread is also way more active then the ones on the moped army.

[Jlugo]

Have you ever converted from the acid battery to one that is rechargeable instead?

[typeone]

I can tell it turns over but i'm not getting spark. I'm assuming thats because the top head needs replaced since i've tried a new sparkplug. This thread is also way more active then the ones on the moped army.

i put a new coil on it right away since the OEM unit had a crack in it. still worked but maybe start there (?) i also did a new plug

Have you ever converted from the acid battery to one that is rechargeable instead?

no, i replaced the stock battery but i don't need it with my current setup. it's been dead for years.