Paul1574

It’s an open foam air filter not a pod

I have a yamaha aerox 50cc 2t liquid cooled and all the lights except brake and indicators keep blowing. They've been fine but started playing up yesterday. I was about to leave work and it was starting to get dark and no lights were working, checked my indicators, brakes and full beams and the brakes and indicators worked but the full beams didnt. As I was riding along the speedo bulbs went out slowly 1 by 1. They arnt just popped or anything theyre completely melted of and no filament left. I held the brake lever a tiny bit so the brake light would turn on but the brake wouldnt apply and it worked and I got home. Went to work today and put new bulbs in (work at a garage). Since I bought it the lights have been really dim at idle then brighten up when I rev the engine. When I tested them today they wouldn't actually turn on unless I revved it. I revved it about 6000-7000 rpm and held it for about 2 minutes (on the stand) and when I checked the bulbs they had all blown (headlight, rear light, side lights) but the brakes and indicators still worked. Done some looking at the wiring diagram and from what I can see the headlights, sidelights, speedo lights and rear light bypasses the voltage regulator. But the brake light and indicators don't from what I can see. There is a resistor but I'm not sure what that really does. Was going to replace the regulator but dont think that has anything to do with it. https://www.manualslib.com/manual/1102634/Yamaha-Yq50.html?page=153#manual (wiring diagram for if anyone wants to look) https://www.manualslib.com/manual/1102634/Yamaha-Yq50.html?page=154#manual (lables for wiring diagram)

Has anyone had a problem with removing the little hoses between cylinder and carb and putting blanks? What kind of temperature would cause a problem I think it would run better without because it would be cooler air so more power

Put 4.5 gram rollers in instead of the 5 grams I had before and it’s all a lot faster I think I got about 60mph out of it. It dies a bit from 33-38 but I can live with that for a little bit. Getting a new air filter for it so going to get it all setup perfect then

Buy all my stuff from ped parts just found they do dyno tests with all different parts to show you how they work

also just noticed i was wrong it has an 80 jet not a 90 i never actually checked it after buying it but i thought i bought a different one.

Okay do you know what rollers aerox has stock? It has some 5 gram ones in but I think old owner put them in Also ive looked everywhere and cant find it. Does the fuel/air mixture screw mix it throughout the whole time or just at low revs? I somewhere that it just does it at low revs and now not sure

The uprated spring that ive been using is a bit taller than the stock one could it be preventing the clutch to open? https://gyazo.com/426f853db86bdec341ef80b2590d3761 Heard running too rich can cause power loss could it be running too rich? I put a 90 jet in because that’s what I’ve seen people use the most. Any way to stop it or is that just something you live with?

I set it up similar to how I’ve seen others set up I was going to check all the rollers and spring and everything at the weekend It’s got no centre stand so it’s quite hard to work on the bracket for the side stand has been bent too so don’t have that either just have a jackstand under a bit of frame to hold it up Was riding it today and it would get to about 30 (very slowly) then wouldn’t want to go much faster. If I got down over the handlebars (to reduce air resistance) it would gain a bit of power and slowly crawl it’s way to about 40 then I think the power band would start kicking in a bit so I’d sit up again and it would go past 50 but by that time I’d run out of road

Air seal ally kit? Are you 100% sure it will be fine if I just ride it normally now? Dont gotta heat cycle it or anything like that? Didnt think i had to till someone told me https://www.pedparts.co.uk/product/4202/airsal-70cc-sport-cylinder-kit--yamaha-aerox got that cylinder kit

how long would you say would be good to run it in? ive been told you should go 30-35 for 300 miles I have a Sym Jet Euro X 2004 too with tecnigas exhaust on and acceleration on that feels alot better than my Aerox. Put my hand over the exhaust for about 1 to 2 seconds to check if it was blowing and its very very oily wasnt sure if this is correct. after about 1 second i have a thick black circle on my hand. When it gets to about 8mph it revs really loud then calms down and accelerates. It sorta has the feeling that something is holding it back. If i slowly turn the throttle while accelerating it doesnt make the loud revving noise but accelerates about the same.

Got a 2010 Yamaha Aerox as a project and had to completely rebuild the engine. Fitted a full circle crank shaft, 70cc Airsal Kit, 17.5mm Carb with 90 jet, 5 gram rollers, 30% spring (not sure if thats correct for what I'm running), Uprated crankshaft bearings, Lighter Clutch, Vented performance clutch bell, Double layer Polini air filter, Kevlar belt, new reed valves. It feels like it is lacking power from watching videos where people have the same cylinder kit but not full circle crank they seem to have better acceleration. I'm going a bit easy on it because I gotta heat cycle the engine so im not going over 35 and im accelerating slower but when i do try it seems to have nothing. Also if im at about 20mph and accelerate it takes years to get to 30. If anyone knows anything that could help please reply. Forgot to add to the list I have a Technigas Q-Tre exhaust too.

I think its the fuel filter/tap because its fine unless its high demand

Bought a yamaha aerox off a friend that has been sitting for about 4 months. They bought it for £600 and in 2 weeks it broke down turns out the side stand got bent and went through the air filter then before he noticed that he jet washed it. He didnt know anything about mechanics and couldnt really be bothered to get it fixed and pay for it so he just left it sitting. I bought it off him for £90 and got a new air filter. I also removed the exhaust and because it was so rusty from being old it snapped in half so I bought a new exhaust (Technigas Q-Tre). After kick starting it for 4 or 5 days for hours straight it suddenly started up and was working and everything but was very slow. I took it to get an MOT and it passed as had not done many miles since last MOT. After some research I found out that the exhaust had a restrictor in it to keep it going 30 by restricting the engine. I took the exhaust off and removed the restrictor and it would get to about 40 but still took ages to get there and would drop to 25-30 up hill. I rode it to work 2 days (about 20-30 minutes mostly just a straight road) on my way home on the second day the engine completely cut out (about 10 minutes after I left) and I managed to get into a little side road. I tried kick starting it a couple times and it wouldn't go then after about 10 more times it started and seemed fine again so I carried on riding it trying to be careful and just get it home but then the engine cut out again and when I went to kick start it back up it wouldn't even move because the piston was seized. I got someone to tow me home and I took the reed valve out so that I could see in the crankshaft and after removing the CVT cover too I could turn the crankshaft back and forth a little bit and it was all smooth so the piston was seized into the cylinder. I ordered a 70cc cylinder and took the old one out. There was not a single scratch or mark on the old cylinder or piston other than marks on the top of the piston from where I had to hit it with a punch and hammer to get it free from the cylinder. I put the new cylinder and piston in and got new reed valves as they were quite worn then I went for a ride and after about 10 minutes again as I slowed down it turned off and was seized up again but this time after about 5 minutes it was all free again so it had only heat seized but why? The thermostat is opening because coolant is circulating back to the radiator its not running lean. After alot of googling and watching videos i found out the 2 nipples on the top of the cylinder and 2 on the side of the carb are for 'carb heating' so that in cold weather the carb doesn't get icy or anything if some water vapour gets in. After connecting some hoses to the carb (used clear ones so I could make sure the coolant is all getting there and everything) I also put a connection on the temperature sensor wire as that had broken off. I then went for a ride and it was perfect I went on a ride for about 15 minutes and didn't have a single problem with it. The next day I went out again on a test and after about 10 minutes of riding I decided to test it in a straight line to see if it could cope constantly going instead of slowing down then speeding up so I went down the main road near me and was still not very happy with the speed only getting about 38. After about 5 minutes of riding it started choking and spluttering and losing power so I pulled over and turned it off then checked about and it seemed fine so I tried starting it and it seemed fine again so I decided to carefully ride it about 3 minutes home and had no problems with it (going about 30). I am an apprentice mechanic and have spoken to the people at work about it (who have been doing mechanics for over 40 years each) and they haven't got a clue what it could be one of them even used to do 2 strokes he doesn't know what it could be either. It still has the 12mm carb was going to get a 17.5mm one next time I get payed but could it be the coil pack? Had a new Drive belt, Intake manifold, Air filter (box and filter), Reed valves, Spark plug, 70cc Kit (Cylinder, gaskets, piston, cylinder head), Main jet (was 80 when i bought but meant to be 62 and worked it out to be about 74 so put a 75 in), 5gram rollers, Side stand. Please help

put a 75 jet in (what it should have) and it was working fine didnt see any problems with it but then I went to test how long it can keep going in a straight line for and it lastest about 5 minutes then started choking I connected the temperature wire on because that was broken off and had been since i bought it and no temperature lights came on. Could it be the spark plug or coil? It was also quite wet out i left it about 30 seconds then it started first kick and didnt have any problems with power or anything on ride home

I put it all back together and put an 82 jet in which i think is still a bit big but its better Im just testing it. I left it idling for about 20 minutes and it was completely fine I couldnt test it because it was snowy and icy but going to test ride tomorrow ill tell you what happens.

It’s an airsal kit but before that it had the stock one on i think it might be cold seizing which is where the piston expands quicker than the cylinder when you don’t let it warm up enough and when you put loads on the coolant is still keeping the cylinder cooler then the piston expands and seizes in

I didn't realy want to do the crankshaft because you gotta split the engine. The crankshaft is all moving smoothly. When I was going to put the new kit in I took the variator and everything off and I took the reed valves off and could see the crank shaft and bottom of piston and I could move the crankshaft round about a cm from each side or something and the piston wouldnt move so the crankshaft was all fine and everything it was very smooth the piston wouldn't move though

The old piston and cylinder look fine no scratches or marks you wouldn’t even think that it could’ve seized It has a new good brand 70cc sport cylinder in it and on first test ride that heat seized Had new Reed valves as old ones were quite worn out. Had new cylinder, cylinder head, piston all that. New intake manifold. New air filter(and box). New spark plug. Fresh 2 stroke oil. New jet. Does anyone know what could be causing it to heat up to much

At the start of summer my friend bought a Yamaha Aerox for £600 and it worked pretty much fine but 2 weeks after riding it, it wouldn't start. I do motor mechanics on cars and I've fixed lots of broken mopeds in the past. After it broke down he threw the air filter away and said 'It's f*cked'. I recently bought it off him for £90 and spent ages getting it started then the kick stand went through the new air box I had just bought so I asked him and he said that happened to him as well so that is why it broke down because it got all wet. I got a sports exhaust and it was running fine i got it MOTed and used it to go to work but on the way home last Tuesday it stopped getting spark or something and the engine turned off. I stopped at the side and looked at it and didnt see anything wrong with it so I kick started it about 10 times and it started up and seemed fine so I started riding down the road again and it stopped again after about 5 seconds and this time I went to kick it and it was completely seized. I got someone to tow me home and the next day took the cylinder head and everything off. I had to hit the piston with a hammer to get it to go down through the cylinder. After taking it all apart and looking at the piston and cylinder it all looked fine I've had people that have been mechanics for 40+ years and they have said they look fine. The piston was definitely seized because I could move the crankshaft back and forth a little bit but the piston wouldn't move in the cylinder. I ordered a new 70cc sport cylinder and piston. I searched everywhere and found out it could've been running lean as I didn't re-jet it when I got the exhaust so I got a box of jets 68 - 82 or something because the stock jet is meant to be 62 from what I found but when I opened the carb I found out it had a 80 jet in it already. I bought another set of jets 90 - 108 and fitted the new 70cc cylinder and put a 92 jet in because running rich doesn't cause as much heat. I also got a new drive belt after fitting it all I started it up and it started first kick but sounded like absolute sh*t. After showing people a video of the sound they all said it sounded like a truck or tractor but when I put my phone near the exhaust it sounded like a 2 stroke. I went for a test ride and was out for about 5 minutes then went to turn around and as I slowed down and turned it stopped again and It had seized once again so I got someone to tow me home again and when I got home I pushed the kick starter down and it was nice and free so it had heat seized. There is 2 nipples ontop of the cylinder and 2 on the side of the carb that had blanks over them and I have recently found out that it is for carb heating. I found a hose that would fit over and took the belt off because I thought it was the belt or clutch making it sound bad and it sounded better but still not the best it and it was very smoky. After running it for about 30 seconds my whole garage was full of smoke. I learnt at college last year that white smoke can be unburned fuel but I have got a brand new spark plug on it. What could be causing it to be heat seizing? What could be causing the sound? Is there any point spending more money on it? What could be causing the smoke? (its white smoke btw but its not coolant because it doesn't smell coolanty(sweet) it does smell a bit fuely)