Jump to content

Search the Community

Showing results for tags 'YZ'.

More search options

  • 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
  • ATV / UTV
  • Inside TT
  • 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 NV Desert Exploration'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
  • 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


  • 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



There are no results to display.

There are no results to display.


  • 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 NV Desert Exploration's Stuff that happens on a particular date
  • 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
  • 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
  • North GA Trail Riders's Ride Calendar

Find results in...

Find results that contain...

Date Created

  • Start


Last Updated

  • Start


Filter by number of...


  • Start





Website URL






Found 24 results

  1. Hi guys, Picked up a 2000 YZ 125 in pretty good condition, but wanted to look into swapping out the Athena Factory kit on there with a OEM cylinder and head. I know the Athena kit uses their own power valves so I'll need to source the OEM ones, but all the other hardware is the same. Do power valves wear out, or am I safe buying a lightly used set on ebay for this part? The cylinder and head I'll be buying brand new. Thanks in advance guys. Edit: My goal is to basically restore this bike back to nearly new condition. I’m willing to spend some money, possibly more than it’s worth to some. Ultimately I wanted a rock solid green sticker 125 to thrash on all year so bear with me. Small airbox leak by previous owner let dirt into the boot so I’m doing a flush at the bare minimum. I have not even started the bike since I purchased and did my internal inspection. Splitting cases soon down the line to check and replace bearings and seals.
  2. Hey TT! You all know me as that one annoying 15 year old kid that rides dirt bikes on the street for YouTube content. Well I bought a 2002 YZ 125 that had no compression, and I got it for cheap. So, today I fixed the float and went for a ride, but felt like enough was enough. I called my dad to come and help me take off the top end, and so we did. Be aware that I am a 15 year old kid, that has no experience with top ends, and am basing everything off one 17 minute YouTube video that was watched two weeks ago. Anyways, here's how it looks. Now here's my question... What size will I need to purchase? It is a 53.96 currently. Also, will I have to bore it out or is it good? Posted pics of the cyinder too. OR, I can do the 144cc kit. Eric Gorr is charging $450-$500 which is too much, any cheaper alternatives? Gary, where are you?? Two Stroke YZ Doc I need your help man! Thanks!
  3. Has anyone tried using Athena power valves in an OEM cylinder? Everywhere it states "for Athena cylinder only", yet on Amazon, it states that they're good for both OEM and Athena applications. I've seen both (not side by side, unfortunately), and they looked pretty similar. Didn't take measurements, although I should've. I have read of people trying this but not actually running it. Just was wondering if anyone has experience with this. Thanks in advance!
  4. I want to buy a clutch cover for my 2018 YAMAHA YZ 250X. What do buddies suggest to me? Which is the most resistant and beauty? https://www.ebay.com/itm/Boyesen-Clutch-Right-Side-Crankcase-Crank-Case-Cover-Yamaha-YZ250-YZ-250-X-99-18/192766151573?fits=Model%3AYZ250&epid=171142106&hash=item2ce1c20b95:g:gIQAAOSwlx9cHRIg http://www.boyesen.com/works-billet-factory-racing-clutch-covers-4.html https://hinsonracing.com/product/billetproof-clutch-cover-yamaha-yz250x-2016/ https://www.motosport.com/gytr-billet-clutch-cover?variant[GYT0017]=GYT0017-X001-Y007 https://www.ebay.com/itm/Tusk-Billet-Aluminum-Clutch-Cover-Black-YAMAHA-YZ250-YZ250X-2001-2019-yz-250-/173746044311 Other suggestions? Thanks.
  5. I sent off my cylinder to be bored and coated and when I got it back, it doesn't look like they decked the cylinder. When I set the cylinder head down flat on my granite flat slab, it rocks back and fourth a little which is an obvious indication that it's not flat and straight. Will that make a difference once it's bolted down and tight? I know you can put 400 - 600 grit sandpaper on the granite and sand a cylinder head flat but can you do that with a cylinder itself? Are there any measurements people know of to test this? The manual says nothing about it nor does it have measurements for it. It's not crazy out of spec from what I can tell, I just don't want to grenade this thing after spending so much time and money on it. Just some insight would be nice.
  6. I am in search of a pan head screw for my 2001 yz426f. Every local shop I have called and every online parts store I know of has it as discontinued. The part number is 3TJ-14325-40-00. Has anyone heard of a replacement for this screw or a place I can buy one? Thinking maybe a screw off a different bikes carb will work but don't know where to start looking. If I can't find a replacement I guess I'll just buy a new carb but really hoping to find the cheap option here!
  7. Greetings, I have broken 3 of these shafts on my 2003 YZ450F. I am wondering if there is a combination of parts i can buy to convert it into a newer shaft or if a newer shaft will fit? I know I know, i shouldn't start the bike with the throttle open, but its force of habit as being an old school two stroke guy. I purchased a complete assembly off a 2006 and it will not fit in my case, it is 20mm thick not 16mm thick like the 2003 shaft. Also if anyone is selling some parts, i am interested. Any help is much appreciated.
  8. Which bike should I buy. A 2007 YZ250F Is mint and has a fmf pipe and an extra set of plastics. It is for sale for 2800 CAD. My friend is willing to sell me his 2003 cr 125. It is 100% mint and has 30h on a complete engine rebuild. It is for 2500 CAD. Which bike should I buy?
  9. NO HATE OR SMARTARSE. Hi all, i have recently bought a 2003 yz250. I have gotten it freighted so i have only looked at photos and a video of a start although, those don't prove much. I have a couple of questions if anyone can help me please do. If you have had the same year or similar and model please tell me what you ran? PLEASE NOTE - I LIVE IN AUSTRALIA. 1. Because i have gotten it freighted, the fuel has been drained. A mate wants to test the gears and some other stuff, so i am going to buy 3l of fuel to test, what ratio should i mix at and what fuel and oil should i use? 2. I'm riding in the bush with a couple of mates on 250 2 strokes, there will be quite alot of dirty,dust,rocks etc, what would be the best air filter and oil? 3. I wouldn't consider myself a pro rider but, I ride fairly hard, I want the bike to be healthy and in good condition. I don't want to replace the top end for at least 40+ hrs. What would be the best fuel to oil ratio, and what would be the best fuel and oil to mix with? 4. I plan on doing a top end, service, power valve and carb clean and maybe add v force reeds (if gears and the other stuff are good) Watched a couple youtube videos of top ends and they look easy, power valve looks a little hard but i think i can do it, have never cleaned a carb on a 250 so not sure what to do. If i added vforce reeds would it need to be jetted? (Don't know how to jet either) Think that is it for now. I LIVE IN AUSTRALIA.. Thank you
  10. I have been looking for alternatives for lighting on this 2017 YZ 250 2t. No current electrical stator maker / re winder has anything for it, in stock or available in the forseeable future from suppliers in the Orient. Some are listed, but only at 35Wt., and yet, still don't have them to ship. I'm told by Baja Designs, that they had a lighting coil for a 2004-2006+ that might work. So, I have set about the task of asking around to see if anyone might have something like that laying around. If not. . other suggestions.
  11. Moderators relocate if needed I know someone on here has the answer and possibly the parts I need. I bought on Craigslist a WR426 street legal with 17’s and also the stock wheels. I gave $950 for it so you know it needed some work. I have went through most everything on the bike so far and it’s about 90-95% now. I have been trying to find replacement fork caps for it, one cap has been rounded off from wrong wrench or something and the other has a frozen clicker that I cannot free up. I have changed the springs for my weight and bushings/seals ,oil by using channel locks carefully on the outside edge. I cannot play with the settings because of the clicker and the rounded one drives me nuts looking at it. What years/models will interchange? I don’t think they are worth what eBay wants for used ones, like 75% of new, the only fair prices so far have been for only 1 and I want the pair. I have posted here on the classifieds but no response because I think everyone is there looking to buy. So let me know what other models I can look to for replacement, much thanks in advance.
  12. Hey TT. I made a thread titiled "2002 Yamaha YZ125 Top End".But I am going to be doing more than a top end, so I made a new thread. YZ Doc has been very helpful by the way. While dissembling the bike, I saw that the Forks were leaking oil. Can I just run it or is that bad? How do I fix it? Let me know, thanks. Here's a pic of the bike when I bought it.
  13. I'm researching slider and chain guide combos and am leaning towards TM Designworks, but they seem to have multiple versions and to confuse things none of the retailers I've checked nor TMD's own website compares the various models, e.g., GP, Factory Edition, etc. Any suggestions? TM Designworks guide combo kits TM Designworks guides on RMATVMC
  14. Anyone ever had this happen to them? First practice of the day I got the bike warmed up for 5 or so minutes and pulled off. Second time out the bike locked up in the air over a jump on lap 2. Pulled the motor apart and found second gear in pieces and a lot of other transmission components got chewed up from it. Parts being replaced are: 2nd gear, 2nd pinion gear, 5th gear, shift drum, all 3 shift forks, both shift guides plus all the washers, circlips, and bearings. The bike is a 2011 so should I play it safe and replace the entire transmission since it’s opened and I’m already replacing most of it? I can imagine that both shafts might have been bent slightly and the other gears have the possibility of grenading at any time. Any advice would be appreciated Thanks 2nd gear
  15. Hey guys... so I have a problem... I took the bike at Cal City, broke it in, and while I was doing so, the bike was bogging in first gear (Yes, first gear). Also it doesn't idle at all. I have to keep blipping it otherwise it'll stall. So I adjusted the screw circled in image 1. Well I was listening to the sound of the of the bike, yet the rpm's weren't increasing, and it was still stalling. So then, I unscrewed the screw in image 2, well I found out that it was fully twisted to the right. So then, I twisted it to the left, still nothing; it was still stalling... where's the idle screw? I am sure that the screw in image 1 is for the air/fuel mixture screw, and the screw in image 2 is the idle screw, just broken? I don't know, any and every help would be appreciated.
  16. Hello everyone. First post here! Hope to stay active. Im making this post as I’ve read a lot about both bikes, checked several threads made here, but unfortunately I haven’t found anyone with similar intentions/riding style as I, to help make my decisions. To start off, a little background: I’m sort of a big dude, 6’1 205 lbs. I’m starting off my 20s and want to get myself a nice new bike. I got my first bike when I was 13 and I would consider myself an intermediate rider. Over the years of riding I’ve only owned a few bikes that lasted me quite while, started on an IT175, then a KX125, and my most recent bike I owned for 2 years was a 1990 XR250R. Bike was an absolute tank. I did ONLY trail riding, never raced and I don’t plan on it either. I’m currently healing due to a very severe compound tib fib fracture (non bike related) and I sold my bike not long ago. So, I have quite a while before I get another bike, and I figured while I’m healing it would be a good time to research and decide what bike would fit me best for when I’m ready to hit the trails again. My heart is set on a Yamaha. Either the YZ250X or the YZ250FX. I’m not crazy fast on trails, and I don’t get into any insanely difficult terrain most of the time. I ride around in silt “fields” and expansive trails that can get pretty rocky sometimes, and I’ll do an occasional hill climb. Northeast Pennsylvania to give you guys a rough idea. When I come out to an opening I will open the bike up, but most of the time I’m just cruising through the woods, so I still want some power. I’m not hard on the bike is what I’m trying to say. I was considering the WR250f but I’m not into lights, as I don’t ride at night and I have no plans on plating it. So that brings me to the two bikes in question. I’ve ridden 2 strokes before, and I don’t have experience on a 250 2 smoker, but like I’ve stated I’m more of a cruiser when it comes to the trails. Which is what had me eyeing up the 250fx. I heard great things about both bikes. That they’re both reliable. Maintenance is a concern here. I’ve done maintenance on both my 2 strokes and my only 4, but I understand older air cooled 4’s don’t need nearly as much maintenance as these MX styled 4 strokes. I know that routine Oil/Filter changes, and air filter cleanings will go a long way to help the longevity on any 4 stroke, as well as considering the fact I’ll probably never hit the rev limiter. My BIGGEST concern is top end rebuilds on the 4 stroke or catastrophic failure. Valve checks aren’t a concern as they seem simple enough. I have done a 2 stroke top end rebuild before and it wasn’t hard at all. Also I’ve heard 4 strokes like to overheat unless you’re constantly moving but I know the FX accepts a fan easily. Or is it even that big of an issue? The electric start on the FX is a big plus, considering my leg isn’t going to be to its fullest extent when healing’s over, but I would like kick in case something goes wrong with the electric. I’ve read that the FX has a very good electric start. Friends of mine have recommended the 4 because, well they all ride 4 strokes, and told me I can lug it when I want but the power is there. The thing that’s keeping me so torn between these two bikes is this. I’ve always liked 2 strokes and their sound/less expensive maintenance but I wouldn’t mind switching to a 4 MX styled bike, and I’ve heard nothing but good about the newer 250fx’s. Praise for both X bikes that is. So, with that mouthful being said, what bike do you guys think would suit me better? Thank you for reading!
  17. Hello, my name is Nick. I'm a 15 year old who just traded his old, beat-up warrior 350 for a complete, non-running 1978 YZ400. I know enough to know that this is one if the best years of the YZ400. I'm going to do a complete restoration of this bike starting with the engine. It kicks over but has no compression. That being said, it is ridiculously hard to kick over and I hear a grinding sound. I just took the jug off and the piston is old and beat up but looks like it would run. The jug looks good too. The rod is not broken and the crank looks intact as well. Even with the jug off it dosent want to turn over. It looks like I can buy all the parts to rebuild the bottom end. I just dont know where to start. I know I'm gonna have to split the cases but I would like the help of all you people with more experience than me. I'm thinking the bottom end bearings are shot but what do you guys think?
  18. My YZ125 won't shift as stated, the problem occured when I took the clutch side case off to replace the water pump bearing and seals. Prior to this it was in running condition. Now I can push the bike, but as I do after say a metre, I hear the piston cycle. When I had the case off, I remove the kickstarter shaft and, a odd shaft something my brother called a power something. The clutch itself didn't come off, but the impeller and shaft did come off. Even with the clutch lever pulled, and the line adjuster it won't shift or roll without resistance or what I assume is the piston cycling.
  19. Hey dudes, looking for some sage wisdom concerning OEM and aftermarket reed systems in general, and specifically for an '01 YZ125 I recently purchased. I need a whole new setup as the original one is totally shot; petals are chipped and look like meth smoker teeth and the rubber coating stuff on the OEM cage is deteriorated. I've done a fair bit of reading about the differences between OEM cages/petals, Vforce 3's, and the Boyesen Rad valve and trying to decide between the 3. The general consensus as far as I understand it (correct me if I'm wrong) is that the Boyesen and OEM setups are pretty well dialed for wide open MX power, putting the power towards mid/top RPM range, whereas the Vforce3 seems to do better down low but sacrifices top end power (plus you typically have to put some damned RTV on the thing for it to seal properly, which is kinda not cool). I'm setting the old girl up for outdoor MX; natural terrain with big fun corners and big fun uphills in a sand/dirt mix with some hard pack, so wide open most of the time. The plan is to enter a few motos in the near future. It sounds like a Boyesen or a new OEM setup is the one for me if what I've read is true, unless the '01 reed valve setup is lacking for any reason (it looks like the motor and reed valve changed once or twice from my '01 to the '06 - present generation of YZ that most everyone is running). Does anyone know if there were any considerable changes to the OEM reeds/cage since '01 that would make the Boyesen or Vforce a noteworthy upgrade for my bike? What about Petals? As far as I understand carbon fiber or stiff fiberglass reeds are best for wide open MX and dual stage reeds seem more geared to offroad/control with more bottom end and a smoother hit. It would seem logical that most people's rave reviews of improved power/throttle response with a new Vforce or Boyesen system might be slightly inaccurate because their old OEM one was trashed (like mine), so obviously a new unit of either brand is going to perform better regardless. I'm curious how a *fresh* OEM system compares to the Vforce and the Boyesen, and I'm primarily interested in what conditions each particular setup is best suited for. Or perhaps I'm way overthinking this and the differences are negligible and I should get the one that comes with the coolest sticker and just ride the damn thing haha Found this thread here from 2013 that was informative but with a bunch of differing opinions, it didn't have too much of the nitty gritty technical info I'm after though: Found this one on VitalMX with similar feedback: https://www.vitalmx.com/forums/Moto-Related,20/Boyesen-rad-vs-vforce3-in-yz125,1288639 I priced out each unit since that's something to consider as well: -The OEM setup on Motosport is the most expensive at $205 (part No: 5MV-13610-00-00) -The Boyesen Rad Valve (Model No. "RAD-33G" for the '01 YZ125) priced at $180 + $20 shipping direct from Boyesen, or $160 with free shipping on Amazon: https://www.amazon.com/gp/offer-listing/B000GZOSKW/ref=dp_olp_new_mbc?ie=UTF8&condition=new OR $150/free shipping from Dennis Kirk: https://www.denniskirk.com/boyesen/rad-valves-rad-33g.p181778.prd/181778.sku -At $142 (don't forget the RTV!) sourced from RockyMountain, the V-Force 3 is considerably cheaper than the OEM and Boyesen setups. So, to put it shortly: What do YOU run bro? Why bro? ***I also need suggestions on what oil to run Thanks in advance!
  20. Just ordered a oem top end kit for my 1999 YZ125. The bike runs perfectly, I'm just rebuilding for preventative measures. Is my cylinder nikasil plated? I ordered a ball hone since my cylinder is glazed. After some research I discovered that honing a two stroke cylinder isn't a good idea because of the ports. I'm taking my cylinder to get measured to see if I'm still in spec. I also will be measuring the ring gap with a feeler gage. Anything I'm missing to make this top end rebuild go flawlessly?
  21. I have a 2018 YZ250x that I use for trail riding and hill climbing, I can’t seem to find a good gas/oil mix ratio for the trails and was wanting some other opinions for this bike, Thanks!
  22. Hello everyone, So I ride trails on a terrain with no hills or anything like that in my area everything is straight just a lot of forests so Im wondering should I get YZ 125 or a RMZ 250 I need something that wont blow up because im 16 and dont have a lot of money something reliable but fun
  23. At the moment I’m in an 85 big wheel and can easily flat foot both feet. I would prefer a 125 but not many are available, whereas 250F’s on the other side are looking closer to my price/availability range than 125s. My only hold back in a 250 is would it be too heavy? I weigh approx 130 lbs (60kgs) and am around 5’9. Would I also be better if adjusting the shock and forks on my 85 and stick with that for longer. Any help would be appreciated
  • Create New...