Took on a job for a guy at work, he let his Venox sit outside for 18 months while he was away and didn't have the means to fix it. Pulled it into my garage expecting a weekend's worth of cleaning the carburetors, but without a manual (in english) and other ongoing projects, 2 days turned into 2 weeks, which then turned into 6 months after i had to go on a trip. After returning, i downloaded a PDF manual and settled in to finally re-assemble this Maroon Menace.
An hour in the ultrasonic cleaner put a whuppin' on the gunk that was in the jets, and an hour each on the carb bodies with carb cleaner and compressed air in all the orifices cleaned those up well. Re-assembly was painless with the manual, with the correct main jets in the correct carb positions. pilot's were the same size. I had labled the floats for their position, and reinstalled in the same carb bodies. But, when i went to set the float level, i had a head-scratcher. The online PDF calls for 19 and 17mm, front and rear. by my calipers, the max adjustment i can go to is 7-8mm before the back of the float pivot bottoms out on the carb body. I figured i somehow swapped floats, so tried switching them. same thing, so i put them back. Now, i'm not a novice carb tuner, been working on my motocross bikes since i was Fourteen, so this is a weird thing for me. Possibly kymco specs a different point to measure from, but from the float bowl gasket surface to the "top" of the float, and the float tang barely touching the float needle, i only get 7-8mm and if i use my finger to make them move more towards 17, the floats cannot go any further and simply stop at around 9 mm.
This brings me to my next weird point, i simply set the floats to where they "looked right" and re-assembled the carbs, installed onto the bike and hooked up my auxiliary fuel tank to start the bike up. starts and runs fine, a few tweaks here & there and it idles perfect. it seemed a little slow to rev up, but this was the first time i heard the bike run, so passed it off as normal. I re-installed the tank, hooked up the vacuum lines and coolant lines (they were plugged for my test run) and took it for a ride to the gas pump. Now, i know it is a 250 but online searches say around 30 horsepower, about equal to my Suzuki savage when it was stock. it felt like a weedeater motor- very poor performance, felt lean. no bogging, but just felt like a main jet was 5 sizes too small. It struggled to maintain 60 miles per hour on a flat road, slight inclines required a downshift and slowed to 45mph, with an obnoxious amount of RPM to keep even that speed. on the return trip, a WOT 65mph downhill run actually ran the bike out of gas. I was worried because it felt like i lost compression, but after i pulled (coasted) into the parking lot, the engine wasn't overly warm, never got the low oil pressure light, and after sitting for 10 minutes it cranked right back up and i rode it home.
Now, a couple questions:
Do any of you have a good pic of the 'standard' kymco float level measuring procedure, or can you confirm my method? I feel like i did everything correctly but it seems like the floats were set too low, resulting in the poor performance and eventually running the bowls completely empty.
Could this possibly be a venting issue? back when it was stock my Suzsucky had issues with the tank not venting properly and starving the carb.
Any other off-the-wall issues with these bikes? i'm new to Kymco, this isn't my bike so i haven't taken the time to learn specific issues related to them. It was supposed to be an easy favor for my coworker, not an ongoing odyssey of troubleshooting!
as soon as i post this, i will be going into the garage and performing a compression check, if only for something to do. I really don't want to take the tank off... AGAIN... i'd rather get started on my other projects.
oh, a final note- no other adjustments were made, the air filter is clean, i didn't touch valve adjustment or timing so it should be the same as before he parked it. The only thing i've messed with is the fueling system. Also, the tank was drained completely of the old fuel (removed the petcock) and fresh, ethanol-free 93 octane was used. What's the deal with this thing?
Rob
