Jump to content

Search the Community

Showing results for tags 'Yz125'.

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


  • Dirt Bikes
    • General Dirt Bike Forums
    • Make / Model Specific
    • Dirt Bike Technical Forums
    • Special Interest Forums
    • Dirt Bike Regional Discussion
  • General
    • General Forums
  • ATV / UTV
    • General ATV / UTV Forums
    • Make/Model Specific
    • ATV / UTV Regional Discussion
  • Inside TT
    • Community Sponsors
    • Advertise on ThumperTalk
    • Site Usage, Bug Reports & Suggestions
  • ThumperTalk Clubs FAQ & Help's FAQ/Help & Discussion
  • Chadwick, Missouri: Information & Riding's Topics
  • So Cal Flattrack's Club Forum
  • Thumperjunkies - Ottawa & Eastern Ontario Riders's Discussion
  • Jersey MX and offroad's Places you ride
  • Jersey MX and offroad's Discussion
  • SE Ohio Riders's Club Discussion
  • NorCal Trail Riders's Topics
  • Northern Nevada Roaming Bastards's Discussion
  • North Texas Enduro Riders's Topics
  • Twistin it in PHX's Introduce yourself!
  • Twistin it in PHX's Discussion
  • So-Cal Track and Trail's 1st club ride coming soon...
  • Moto TnT Track & Trail's Moto Tnt Racing Questions
  • Moto TnT Track & Trail's Rider's Forum
  • Dualspot Riders Orange County So~CaL's Club Discussion
  • Chester County PA DS/Adventure's Im here
  • Chester County PA DS/Adventure's Ride Dates & Times
  • Niagara region's Club Discussion
  • Walker Valley Single Track Riders's Unanounced ride(s) recap(s)
  • Walker Valley Single Track Riders's Supplements & recovery aids
  • Walker Valley Single Track Riders's Bikes maintenance & restoration
  • Walker Valley Single Track Riders's Safety gear & apparel
  • Walker Valley Single Track Riders's General
  • Walker Valley Single Track Riders's Riding technique
  • Sacramento Area Trail Riders's Club Discussion
  • Sacramento Area Trail Riders's Info from another club
  • NC woods riders.'s Club Discussion
  • Colorado US Route 50 Rides's Club Discussion
  • Middle GA Off-Road & Trails's Club Discussion
  • WNY Dual Sport Trail Riders's General Discussion's
  • SoCal JUST RIGHT riding club's SUNDAY 10.13
  • OREGON Riders Club's Club Discussion
  • Glamis bike crew's Topics
  • Glamis bike crew's One last trip
  • Glamis bike crew's Let’s hit the dunes!
  • South Texas Dirt riders's Topics
  • PNW Trail Maintenance Club's Trail equipment and how to carry it
  • PNW Trail Maintenance Club's General Discussion
  • PNW Trail Maintenance Club's Introduce Yourself
  • New England riders's Events
  • SC Dirt Riders's Topics
  • Club RMX's Photos and videos
  • Club RMX's Engine & Engine tuning
  • Club RMX's Chassis, Suspension, & tuning
  • Club RMX's Electrical and electronics
  • Club RMX's Body, fender, & Graphics
  • Club RMX's Build projects
  • Club RMX's Everything else
  • Club RMX's Classifieds
  • North GA Trail Riders's Topics
  • NorOnt Trail Riders's Topics
  • Virginia Supermoto's Club Discussion
  • Kentucky Trail Riders Club's Topics
  • ADK ADV's Notes
  • Pennsylvania Dirtbike Riders's introductions
  • Missouri Dual Sport Riders's General discussion
  • Missouri Dual Sport Riders's General discussion
  • Missouri Dual Sport Riders's Adventurepalooza 2021
  • Missouri Dual Sport Riders's Organized ride section
  • Missouri Dual Sport Riders's Gpx files
  • Missouri Dual Sport Riders's For sale items
  • Yamaha WRz's Topics
  • Crete Boys TV's Topics
  • Crete Boys TV's Topics
  • Long Island Dirt's Ride Planning


  • Powersports Gear & Apparel
  • Universal Parts & Accessories
  • Parts & Acc. - Japanese Bikes
    • Honda Parts & Accessories
    • Kawasaki Parts & Accessories
    • Suzuki Parts & Accessories
    • Yamaha Parts & Accessories
  • Parts & Acc. - Euro Bikes
    • Beta Parts & Accessories
    • Husqvarna Parts & Accessories
    • KTM Parts & Accessories
    • Other Euro Parts & Accessories
  • Motorcycles
    • Off-Road Motorcycles
    • Dual Sport Motorcycles
    • Street Motorcycles

Products Categories

Vehicles Categories



  • Speed Through Fitness
  • Moto Mind
  • Test Blog
  • Trail Tales of Enduro in South America
  • Michael File
  • Jason Bohl
  • Cole B
  • Loves dirt
  • RodneyBell
  • Johnnyship
  • Fcr39 jetting


  • ThumperTalk Clubs FAQ & Help's Club Calendar
  • Chadwick, Missouri: Information & Riding's Events
  • So Cal Flattrack's Club Calendar
  • So Cal Flattrack's Events
  • Thumperjunkies - Ottawa & Eastern Ontario Riders's Club Calendar
  • Thumperjunkies - Ottawa & Eastern Ontario Riders's Events
  • SE Ohio Riders's Events Calendar
  • NorCal Trail Riders's Ride & Event calendar
  • Northern Nevada Roaming Bastards's Stuff that happens on a particular date
  • Central Washington riders's Events
  • Central Washington riders's Group ride?
  • Central Washington riders's Events
  • Dualspot Riders Orange County So~CaL's Events Calendar
  • Niagara region's Club Events Calendar
  • Walker Valley Single Track Riders's I love Mondays trail ride
  • Sacramento Area Trail Riders's Events Calendar
  • Sacramento Area Trail Riders's First round of Hollister 2020
  • NC woods riders.'s Club Calendar
  • Colorado US Route 50 Rides's Club Calendar
  • Middle GA Off-Road & Trails's Club Calendar
  • OREGON Riders Club's Club Calendar
  • PNW Trail Maintenance Club's Calendar
  • North County San Diego - DirtbikesWithDad.com's 2020 Calendar
  • Club RMX's Calendar
  • North GA Trail Riders's Ride Calendar
  • Virginia Supermoto's Club Calendar
  • Kentucky Trail Riders Club's Events

Find results in...

Find results that contain...

Date Created

  • Start


Last Updated

  • Start


Filter by number of...


  • Start












  1. Hey guys, I have a problem with my 1998 YZ 125 leaking fuel. Long story - but here goes. When I picked up the bike from the shop, shop said they had to mess with the float twice to get it right and to stop leaking fuel. THey advised the Petcock is bad. It does not shut off and has a reserve switch, so it is not stock. I rode 3-4 hours through the trails, ran great! Last night I washed it - gassed it back up. Warmed it up, a bit of smoke, but i figured it was just warming up I ran it hard on the pipe 1st, 2nd and 3rd. I started getting some bogging issues, then it died - flooded. With the bike sitting up right and level, fuel started pouring out of the overflow on the carb. I had no way to shut it off since the petcock doesnt work. I had to pull the fuel line and put a cap on it. I have the carb pulled and clear of fuel. Will be checking and inspecting parts here hopefully at lunch time to report back my findings. My question is, since the petcock does not work, my bike was sitting for almost a week with the fuel basically turned on. Will this cause my carb to leak out the overflow or is it more likely the floats were never set right? I don't want to get into changing jets etc b/c it ran so good last week. I don't see any in-line fuel filters or any filters on a replacement petcock. Looking at one of these: http://www.amazon.com/1992-2004-1993-2004-1998-1999-2001-2002-2003-2005/dp/B017J91CLA/ref=sr_1_1?ie=UTF8&qid=1463581375&sr=8-1&keywords=yz125+petcock Thanks!!
  2. I just bought a 2001 YZ-125 2 evenings ago.. I flooded the motor by accident by leaving the fuel on overnight and trying to start it up in the morning.. Had to spend about 30 minutes Bump Starting it to get it going.. Was going to change the oil and the spark plug as a result of flooding it to hopefully get the engine running more reliably and starting easier, but the drain plug was crazy torqued from the previous owner and this happened... Any idea of what i can do about this? I literally just spent $1800 on this bike, $250 on stuff for the bike, and I'm just a college student who spent his summer savings to buy his first motorcycle. I'm all sorts of flustered and pissed off right now, if y'all cannot imagine. The bike has been difficult to start since I got it, and there are a fair amount of metal shavings in the oil.. I have no idea what to do, especially since i have no form of transporting the bike anywhere, nor do i have a trailer hitch to rent a motorcycle trailer for U-Haul.. Any helpful ideas?..
  3. Bought a YZ 125 last week, my son was riding it around for a few days with no problems. It ran out of fuel that was in the bike when we got it. Person we got it from said he ran it at 32:1 but I don't know what oil he used. I bought BelRay synthetic two stroke mix and made a batch. I mixed 8 ounces with two gallons of 91 octane non ethanol (32:1) put it in the bike and within 10 minutes it fouled the plug. Installed a new plug in it (BR9ES) and it fired right up, but fouled it again in 10 minutes. Don't know what's going on here. I believe 32:1 is a good ratio, but maybe the BelRay oil needs to be a different ratio? Thoughts? I have no idea what the jetting is without taking carb apart. He trail/open field rides at about 800 feet above sea level. Thanks
  4. I will be entering my first hare scramble this year, in the beginner class. I have two bikes in my garage, which one would you take? Stock 2001 yz125 2011 wr250r de-restricted with pipe and fuel programmer
  5. Hi guys, If you have been following my other thread I was in the process of fully going through a 2005 yz 125. I got it put back together and it started up. Rode it around the house, and came back to put it away. Before I shut it off I was going to check the throttle response. So I was idling it, and then went WOT. It bogged out and I have not been able to start it since. Actually I got it to sputter with choke on once. That was a while ago, and now it won't even try to start. I even ran it up to the top of the hill and tried to bump start it. That didn't even work. Has 180-190 PSI compression. Plug is wet. Pretty sure its getting flooded. My carburetor settings are 4th clip (I think I went the right way) 2 1/4 turns out on the air screw. Any ideas?
  6. Hello. I just rebuilt the top end in my 2003 yz125 and replaced the piston, ring, and gaskets. During the rebuild, I noticed my cylinder didn't have much cross-hatching, and wasn't long for this world. I have had it running for about 3 months,and yesterday it died and wouldn't kick over, leading me to believe the cylinder finally went to heck. Does anyone know a place to pick up a cheap one? Thank you
  7. I’ve been looking for a YZ125 and been doing research on what the changes are and mods that can be done. I’m more knowledgeable in the 2005-current range, but am probably going to end up getting a steel frame due to cost and availability. So now I am trying to figure out what can be done to them to make it what I want. 1.1) I would really like to do the 2015 body conversion (maybe Cycra so I don’t have to change the air box). So for that I read that it can be done on 2002 and newer because that’s when they started using the subframe that current bikes still have? Please verify. 1.2 )Is there any big benefit in going to the new 2015 air box? Does it make more power? 1.3) Can the newer subframe be put on the older bikes so they can use the body upgrade? 1.4) On those 2002+ bikes (with current subframe), can the newer seats bolt up to give the flatter seat? 2) I know in 2002 or so they switched to a 5-speed transmission and people generally prefer the 6, but with mods (mo-betta 144, Smartcarb) would it be much of an issue? I feel like if you can widen the powerband, rather than going for top end power, the 5-speed could be nice (less shifting). 3) From what I was researching, it should be a direct bolt on to put the SSS forks on the older bikes, by using the newer YZ125 or YZ250F triples, wheel and brake. But, what about the shock? Will a newer (2006+) shock bolt up no problem? It would be nice to have the large shock shaft, Ti spring, Kashima (some years?), bottoming bumper, etc from the newer shock. 4) This one is a long shot. But I heard the cylinder didn’t change much in the 2005 redesign of the engine. Will it bolt up to the newer cases and is there much benefits? I know the 2005+ was supposed to have gained a lot more low-mid making a nicer powerband, so it’d be cool to get that on the older bike. 5) Has anybody ran a Smartcarb on their YZ125. I heard of fitment issues (boot rubbing on shock spring) but also know there has been people using it. How was fitment dealt with and how much did it help low and mid pull? It's supposed to help with low rpm bog (pull rather than bog down). 6) What other parts are interchangeable to be noted? Pistons, clutch basket/plates, wheels, etc? 7) Are there and FMF Gnarly type pipes for the YZ125? Maybe not even that extreme, but something for broad low-mid-top and not just top end pipes? DEP Torque pipe seems like maybe the only option? 8) I read that a newer YZ125 pipe can be put on, but requires cutting and welding, so not really an easy option, and rather go aftermarket anyways. But, are silencers interchangeable? Please knowledgeable people, help me and anyone else looking to buy an older YZ125. Here are some links I have used in research and found useful: Aftermarket parts thread (good ebay deals) /topic/1031539-yz-aftermarket-thread/ 2015 bodywork update retrofit /topic/1102736-so-if-i-wanted-to-fit-2015-bodywork-to-my-yz250-2st-2008-model/#entry11870286 Aussie YZ144 with modern updates and custom work /topic/863092-aussie-yz-144-project/page-5?& SSS on 2001 /topic/946288-sss-suspension-on-2001-yz125/ YZ set up and jetting database /topic/771713-yz-2-stroke-set-up-database/page-1?hl=+yz144
  8. So I have been on the market for a yz125, and found one for $1850 I like alot but i only have $1400. I texted him and just asked cause it couldnt hurt. He said almost with no haggling he could do $1600. Next i asked if i could give $1400 and a trade to cover the rest. He didn't respond for hours then said, its in __ city ready to test ride out of no where. I said I'm about 3 hrs away so its a far drive and he said immediately that he would be up where i am in a few days and could take the bike up. I said, well i don't have $1600 so unless you're willing to accept $1400, i cant do anything. He then said he would sleep on it. I have no idea what to think, also i know its pretty standard but theres no title. It all just sounds kinda sketchy. Should i be worried? I don't want to get mugged or end up with a stolen bike...
  9. Hey peeps, So I've had my 2000 yz125 for a while and came across a nice 2007 yz250 for a decent enough price. So after a quick check to make sure it is what it is I bought it 🙂 I had to get some work done on the carb and thanks to this forum and "in chains" (ringwood) the bike doesn't pee fuel from the overflow anymore! I really wanted your opinions on how these bikes feel and go - sounds weird but I haven't ridden a 250 2t for about 20 years - I was 15 and it was a 88 cr250. I remember it literally snapping my arms off and this bike doesn't do that to me. Now... Yes I am 20 years older (and 90% fatter) so maybe it's me but when ever I get on my 125 it feels quick and revvy. Ride it like you stole it! Is what I have been told and for the 125 it's like that, opened fully screaming and feels really involved. The 250 feels so much tamer. So the 250 has a vhm race head, fmf gnarly exhaust and shorty silencer. The power hits from the start and will easily spin the back wheel and wheelie in 3rd and 4th pretty easily. 5th feels like another 3rd! But it's all low down and ends pretty quickly. So by my description I should be happy but it doesn't feel as "urgent" as my 125 and I swear the 125 has a higher top end speed (not many people care about it but Id like to know it's normal). The compression is just a notch under 200psi which I believe is good. Don't get me wrong it feels massively torquey but I just can't shake the feeling there should be a bit more up top. Have 2t 250s changed a lot since back in the day? Should I be looking at something on the bike to see if I can improve top end or am I just being weird! Ps - the suspension is so much better than my 125 2000 🙂 Cheers peeps pics below of her
  10. Hello, I am curious about what you guys think I should get as a woods bike for riding tight single track in south Missouri (Chadwick). It will be for rocky single track riding in the woods. I have ridden a 2011 kx250f on these trails and found it very difficult to navigate the rocky terrain with a heavy bike. I am 5’ 11” and weight 135 lbs and get very tired when I have to muscle the bike around in the woods especially on long hill climbs. I would like something lighter and I’m debating wether I should get a crf150rb and outfit it for the woods or just use a 2005 yz125 as my bike of choice. Upside is that I have a really nice yz125 I can start to covert for woods riding. I have heard good things about the crf150 but I’m afraid there will be to much modification required to make it comfortable to rip in the woods. What do you guys think? The crf150 will be lighter than the yz125 which is a plus.
  11. Hi Everyone I am buying a new bike. I am stepping up from a KTM 85 BW hopeing to get a yz125 or a Ktm 150/125sx. I do mainly enduro riding racing state series. Whats the best for me? I am obsessed with 2-strokes. I tryed a 250f and I would much rather a 125! I will be buying second hand. Years I am looking at vary from 2005-2016. i am not loaded with cash though. What should i put on it? Maybe a Flywheel Weight, bash plate/s? Will definitely Consider anything you guys say and thanks foir your help.
  12. Should i replate my oem cylinder or can i get an athena standard bore 54mm(not iversize). If i get athena i can sell my oem cylinder. Is there any benefit athena has over oem?
  13. Hey guys I just bought a 07 yz125 with a EG 144 kit. it's set to run on straight race fuel and that can be quite expensive when ripping a lot so I was wondering if I could buy a new cylinder head or something to lower the compression so I could run it on standard pump gas. I was looking at a athena cylinder head because they make 144 kits so I was thinking I could buy a 144 athena cylinder head but I'm not sure if thatll fit my cylinder or work correctly with EGs 144 kit. Thank you guys
  14. First new topic! Any one ride a 125 or 200 for woods/trails and want to discuss pros and cons?
  15. Hey all, I have been waiting for this day for quite a while. I am finally able to fix my bike, i've been in debt for some time but the day has come 🙂 Now i have a question, when I got my bike checked out at the shop, i was told i could rebuild my crank with any rod and bearings from 1986-2000. I am going to purchase an entire new hot rods crank instead. Am i able to order any crank from 1986-2000 for my bike? Mine is a 1987. I just want to make sure I am getting the correct part before I spend the money! Appreciate any replies or help. Thanks!!
  16. I bought the bike this spring, was told it was completely stock and trail ridden. I decided to do a top end rebuild after a few rides at the track. (Bike was still running strong but I wanted to be safe). But that's when the problems started. This is when I found that it had been bored 0.080" over. Shortly after doing the top end, the rod bearing seized. So, I fixed that, got little time on it then the top end went again. The electrode burned off of the plug damaging the piston and head. (Running 93 pump gas and dominator 32:1.). So I bought a new head, jug and started running 50/50 89 rec fuel and VP110. The bike has seized again and now the whole motor is trashed. What in the hell is going on?
  17. I have an 02 yz125, and yes ive looked up what kelly blue books said and i think shes retarded cuz there is absolutely no way im selling this bike for 1600. I have put so much money into this bike, and its at the point where its breaking so much i cant ride with my buddies so i need to get rid of it. I rebuilt this bike with a new wiseco top end with the cylinder being replated and painted, new hot rods bottom end, boyesson reeds, water pump repair kit, new grips, new brake pads front and rear, new front brake rotor, new rear fender, new rear fender graphic, new jetting, clutch push rod axle thingy, governor push rod, new air filter, entire kickstart assembly, and all oil seals and such. The bike is actually in the shop now cuz the tranny is all screwed up, the shop said it is probably gonna be 1300 with labor. I cant deal with this bike anymore, i cant take anymore chances. How much do u think this bike is worth? Thanks
  18. Stripped yz125 drain bolt Ok, so I bought a bike a week or 2 ago and I I've rode it once or twice. When I descided to try and do an oil change like I do for every new machine not knowing exactly when the last time it was done. I found that the plug was stripped really bad. At first I tried a socket... wouldn't even grab... them I tried the stripped bolt remover things that craftsman makes and they just ate the bolt..... thennnnn I tried to jb weld a socket to it to see if it would maybe grab and then the jb weld just broke right off.... theennnn I tried easy out and drilled a hole then tried to reverse it out and the damn thing snapped on the hole... I'm out of ideas... next I might try to hit it with a air chisel that might pop it loose. Anyone got any ideas??? And does anyone know what kind of metal the cases are mad of... 2003 yz125 ? Thanks for the help in advance!
  19. I am going to buy a 125 2 stroke, from what I heard Yamaha's are the best. They have a 39.4 in or so seat height and I have a 33-34 in inseam and weigh about 140 pounds. How low could i get the seat height by chopping out foam and the sag of the bike? I don't want to mess with the suspension or use tiny wheels or anything like that. I don't want to look like this hahaha
  20. Hi All, Every time I pull my bike out (every few days) and turn the petcock on I can hear the fuel enter the line and fill the bowl. This leads me to believe it is evaporating in the carb or entering the engine. Is this a normal?
  21. Hey fellas im just finishing my yz250 project and just got polisport restyle kit plastics for which i need graphics.So can anyone give me vector for them so i can draw my custom graphics in corel?Thanks
  22. So I have an issue, I recently rebuilt my yz125 and then engine got taken out. The motor runs fine just like before but the clutch doesn’t. The actuator arm which is moved by the clutch lever on the handlebars keeps returning to the wrong position and isn’t activating the clutch making it separate. The clutch lever is loose and doesn’t have the clutch feel. Not too sure what’s going on here with the actuator arm but I need to figure it out. If anyone can provide some help that would be greatly appreciated!! As you can see the actuator arm is in more of a 1:00 position rather than the 3:00 or the 90° position it’s supposed to be in.
  23. Just got a 2006 yz 125 and have been riding has rode good, but yesterday while riding i felt the bike pull a bit while just coasting then the bike made a loud popping noise, so i grabbed the clutch and then when i let off the clutch the bike immediately jerked and stopped, after that it was hard to start and after it finally does start now it makes an awful and loud metal on metal grinding noise, changed the oil to make sure it wasn’t that. any ideas on what it could be or what i could check?
  24. 0 comments

  25. 0 comments

  • Create New...