u/drifterig

did a cdi conversion on this early 80s yamaha y80, it was originally on points ignition and those dont like water which i will have to go through on the scrambler race im running, used the stator from the last revision of the y80 that was one of the first cdi system yamaha ever ran, gutted the charge/lighting coil to save some weight and reduce drag on the flywheel magnet, made a wiring harness to run a late 90s yamaha y111 cdi unit for higher rev and better suited timing graph since this thing is ported, gonna be testing on the track really soon!

theres a scrambler/enduro event coming up and im building this to run in the 3 speed underbone class, theres gonna be some 3 speed honda cubs like c70 and some suzuki fr80, 50 laps, gonna be hella fun

added a frame brace and swing arm brace because this thing have some rust holes, also flipped an aftermarket suzuki rc100 exhaust up side down and made it fit, all done by my local fabrication/exhaust shop, he did all this in 3 hours

50 laps around a mostly dirt track with a mud section and some jumps, im signed up for the 3 speed underbone class so theres probably gonna be honda c70 suzuki fr80 and some other 3 speeds, still got a lot of work to do but its coming together pretty nice

(last 2 pics) it was slammed to the ground a while back and i used it as a daily for like 2 weeks until i realize it fucked my back up so i parked it ever since, its nice to turn it into something ridable again

there was a class at this mx race thats for underbones, heard of it the day before the race so i decided to turn a bone stock yamaha y100 i had into whatever this is, did it all that night and went to the track the next day without any testing at all, managed to get a trophy simply because 3 other guys in my class broke lol

i used to ride enduro dirtbike about 6 years ago and left the hobby behind, i actually got another underbone race coming up at the end of this month but its for pre 90s 3 speed bikes so im building a yamaha y80, gonna be a lot of fun!

some random guy in the supercub subreddit told to to take it off the public road after i posted a video of this thing going 160km/h so i guess im just gonna be riding it on this private gravel road now

my 1996 yamaha mate 111 2stroke, currently my daily rider, slightly modded engine with 2.5mm oversize bore, shaved head for higher compression, ported exhaust port, 24mm carb, advanced ignition timing and 15-32 sprockets, still completely reliable and daily usable but will go fast if i wanted to

1996 yamaha y111, bought bone stock to use as a grocery getter but i couldnt stop my self so i ended up with a grocery getter that peg the speedo out, i really hope someone peg me too smh

ported cylinder, 2.5mm oversize bore, shaved stock head for higher compression, 24mm carb, advanced ignition timing, 15-32 sprockets, still running stock exhaust and an opened up stock airbox, 100% street legal but haul ass

bone stock yamaha rxs115cc, only mod is a 28mm carb simply because it didnt have a carb on it when i bought it

1996 yamaha mate 111, held up pretty well for what it is

100 laps on 4km long track, rocks, mud, hillclimb, they got it all out here and theres this guy running a vespa while everybody else are running dirtbikes and scramblers, respect

100 laps on a 4km long track with rocks, muds hillclimbs and all, the winner get $30k which is a shit ton of money here in thailand so its intense, each bike have to go through a checkpoint where they scan the rfid thing every lap and the first one to complete 100 laps win, the rule originally stated that all bikes must be from 1970 or older which i unfortunately do not own but they decided last minute that anything pre 1990 is allowed, i will definitely be out here next year on the track!

still working great as my daily rider and work bike

ik its not a honda supercub but this place seems to be the best to post underbone related stuffs

i run a bike repair shop and also do sand blasting, customer wanted to get his motorcycle frame sandblasted and lived only 2km away from my shop so i took the daily rider, turned out well, made it back to my shop seconds before a storm hit

i run a bike repair shop and also do sand blasting, customer wanted to get his motorcycle frame sandblasted and lived only 2km away from my shop so i took the daily "scooter", turned out well, made it back to my shop seconds before a storm hit

kinda bs you see as a bike mechanic in rural thailand, original filter from like 15 years ago, customer originally asked me if i can just blow it out, i have no idea how it even manage to run at all tbh

was gonna take my truck but there wasnt much so i took the yamaha 111

some might say its the wrong size but i dont think so, this method work even better if its a lithium battery

yamaha y111 2stroke sleeper build, bored up to about 120cc

its not a cub but close enough, one is a big bore yamaha y111 111cc engine swapped yamaha v50 that went 150km/h, another is a bone stock y80 that i cut all the springs off because why not