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Everything posted by sx455

  1. sx455

    best parts for 2005 yz125

    Been thru this get the jetting straight get the jetting straight get the jetting straight!! suspension suspension suspension!! then : stomper lever:vforce reeds:factory fatty w/silencer: 13:50 gearing HOLD ON!!
  2. sx455

    07 yz125

    check with heimens yamaha in minnesota a couple friends of mine got in the crate 06 yz125 for 3950 with shipping they said they still had some left
  3. I think the bike generally come with the clickers pretty much in the middle , we played around with ours, never really felt "right" until had the suspension done, but my kid did only weigh 125lbs, alittle light for the stock spring rates. I havent had to do much with the jetting on ours, i did go up to a 430 jet when it got cold, was running the 410 over the summer, plug always looked good never had any issues with pilot jetting went up 2 teeth on the rear sprocket, but we were running an arena cross series at the time didnt see alot of dif between that and the 48t on a outdoor track, but we were dealing with a 125lb rider the yamaha manual that comes with the bike is invaluable, you NEED to get one. We have had a variety of clutch issues with ours , but my kid is hard on this bike has to be , he generally has a pack of 250fs chasing him:applause: get urself a clutch pushrod to have , its only like 15bux and the tips have a way of breaking off also get the 07 stomper lever, thats an upgrade worth the 10bux or so it cost. the clutch basket , well i splurged for the hinson after 2 looked like saw blades in less than one season, i have stuck with the factory pressure plate cause they are dirt cheap and easy to change . We have also been thru a couple sets of clutch springs and clutch hubs. Normal riding all this may never be a prob, you go racin, now thats a diferent story!
  4. sx455

    400$ to spend on stalk 05 yz125

    On our 05 125 :::: the pc pipe did nothing more than move the power around ie: lost alittle low ,gained alittle mid and top the factory pipe was better all around tried several different silencers,minimal diference at best the vforce reed block?? that made quite a noticeable improvement well worth the money 2 more teeth on the back sprocket-helped everywhere but the very top, but then again ,around here we dont have alot of 6th gear wound out mx tracks. suspension! big difference in being able to use the power that is there.
  5. I have been doing some research on a 144kit for my 14yo intermediate rider. I have contacted Gorr and Moto814, was impressed with the info i receieved from both and their concern for customer service. I would still like some feedback about the Athena kit form individuals who have them. I am not concerned with trying to "hide" a 144 into a oem cylinder, its ama legal and i dont forsee him racing any pro events unless someone puts something serious in the water here in the old dominion. I like the idea of a "bolt on" so to speak, what i mean is, i will still have my oem stuff for emergency or whatever. My son has no probs keeping his 125 on the pipe, isnt afraid of rpms whatsoever. Is an acomplished rider.So, we wont be trail riding so to speak. ANYONE have some feedback on the Athena kit? How is the quality? How is the performance? Will the 144 take the revs like a 125? We ride alot. We have a track on our farm and access to several other tracks in the area, hence, the 125 gets an average of 4-5 hours riding a week this time of year, that may double when the weather gets better. How many hours can i expect to get on a ring, on a piston? I know these are hypothetical questions that have many variables, but someone should be able to give me a ballpark figure. Athena advertizes larger water ports, shouldnt that be a plus over the oem? Thanks in Advance for any help! Rick
  6. My son has a 04 250f . We bought the bike from a local "A" rider . The bike had all the goodies and was fast as heck. The motor was done by a east coast guru always refered to as Coby. End of last season the bike lost compression. I took it down and found the psiton to be cracked. Comparing the dome on the cracked piston to a stock one I had laying around, the dome was considerably higher, so i assumed this was a high compression piston. I was told when purchasing the bike to only run race gas. In reassmbly, i opted for a weisco factory replacenemnt, efectivley lower the compression, FOR 2 REASONS. My son isnt a "A" rider and we ride alot ,i wanted to be able to use pump gas. The head on this bike is a work of art, the porting looks GREAT. I have no ideas what cams are in it. But to the heart of things. Once reassembled , the biken wouldnt run at anything below 3/4 throttle. It popped and spit ect ect . I checked the jetting. It had 172 main 40 pilot. I had a whole nother bike, so i put in the 178m 45p that came in that . the bike ran better but still spit and popped down low and hiccuped when accelerated. i can run the fuel screw WAY out and it seems to run fine,to the point where tI have to wedge the vent hose against it to keep it in the carb. I have checked the carb and cleaned the carb numerous times checkd the float level numerous times. I am assuming i need to fattin the main and pilot up a bit? I am assuming that out on the fuel screw is richer? I have checked for air leak between carb and head ,several ttimes. Is is normal to have to fatten this up so much from only lowering compression?? I have replaced chain and guides , and checked and rechecked that stufff. I am just wondering if lowering the compression would have that much afect on the jetting? Any input would be greatly appreciated! TIA Rick
  7. sx455

    problem with 05 yz125 clutch.............

    I have put several of the clutch rods(?) in my sons 05 the rod that goes thru the case , the tips have a tendiacy to break off. even if that isnt your prob, my warrant checking it out. I also went ahead and put in the hinson stuff, the oem basket and hat just didnt hold up.
  8. sx455

    05 yz-125 what 2 do??

    Hello everyone. Looking for alittle guidance here. My 14yo son is ATE up with mx, has been for several years and has been quite successful here locally. He just moved out of the 85/supermini class this past year and has taken 2 the 125 like a fish in water. I want 2 stay with the 2 stroke cause i think they really fit his riding style and his older brothers 250f almost dollared us out of the mx business. my questions revolve around what 2 do to this bike . He doesnt have any probs running with the 250fs , with the exception of Budds creek, those uphills seem to be a real disadvantage for the 125. I am doing my homework here on some upgrades. What we have now is a 05 yz-125 We had total control respring and revalve for his weight(best mx money i ever spent) New top end with weisco piston and cleaned up ports(no porting ,just remove casting flaws) pro circuit pipe and silencer vforce 2 reed system 50 tooth rear sprocket hinson clutch basket, the stockers dont hold up 2 his abuse well What is next?? I am trying to decide between a 134/139 or 144 kit? He LOVES to zing this thing 2 the moon and is very accomplished at keeping this bike on the bike . I would consider him an intermediate rider, at least here on the local scence. Will the 144 take away the zing factor? I am not trying to make this bike mimic a 4stroke power band, ie: i dont want to lose that 2 stroke zing factor. I have read the 134 or 139 keeps the powerband more like a true 125, the 144 makes it more 4strokish. Are these comments true? He is a very agressive rider , what will fit his style?? Thanks in advance rick
  9. sx455

    yz125 suspension

    Your riding style will play into your suspension setup . A 180lb novice rider may have the same spring ratesas a 150 lb intermedate. start by setting ur sag , that seems to be in the 90-110mm range. then setting all the clickers to the factory settings and ride. play with the clickers a couple clicks at a time ,either soft or hard and see what suites you.
  10. sx455

    05 Yz-125

    My son mx races a 05 yz-125 we bought the bike with only about 5 hours on it froma friend . He had already installed vforce reeds.pc pipe and a 50 tooth rear sprocket. We plan to race the bike again next season. I have been searching the site to get some setup tips. We have already had Total Control redo the suspension Engine wise : he dented the pc pipe so we installed the factory pipe back on he says the bike picked up bottom , lost alittle mid, but was more rideable. From what I have read on hear, the factory pipe seems the hot ticket with a aftermarket silencer? Correct?? I am afraid of the 144, is that logical. I have not found a post yet with any really real world results?? The athena kit looks really promising, but will it be an advantage for a novice/intermediate rider?? Race gas: we have been using 1 gallon of the sunoco 110 leaded race fuel with 4 gallons of 93 pump . Is this a waste ? All the fuel talk i found on this site goes alittle deeper than I care to follow! The bike is stock bore, does have weisco piston (which btw my son claims made the bike rev slower?) THANKS IN ADVANCE
  11. sx455

    05 Yz-125

    thanks for the replys guys. SO, you have to use race gas with the ATHENA? What would U guess the rebuilds at? 10hrs? 20? Would that be a ring or ring and piston. I have read that the 144 doesnt rev ect. ect. ect. I wish someone that has one and has mx raced it would chime in with their comments! I had been thinking about the athena, but they are not legal in schoolboy class,plus we average about 6-8 hrs ride time a week(we have our own private track and access to several others) I would hate to have to rebuild every couple weeks! I could get over the schoolboy thing, but i dont a bike that is a nitemare! Thanks guys
  12. sx455

    05 Yz-125 More???

    My boy is currently riding this bike, he has been having great success here locally, but as with everything he needs "MORE,MORE ,MORE!!" I just did the top end w/Weisco Piston it has vforce reeds,PC pipe and I went up 2 teeth on the rear sprocket What would be logical next step to get that MORE MORE MORE We race MX by the way!
  13. sx455

    05 Yz-125 More???

    When we went to the "big" bike of the 85s , thats the first thing we did , sent the forks and shock to TOTAL CONTROL Thanks
  14. Get ready to freshen up my boys 05 yz125 which piston has everyone been having luck with?? I normally went with the weisco on all his little bikes. This will be the first "freshen up " on this bike. This thing runs so dam good, i would hate to jeopardize that!!!!!!!!! TIA
  15. sx455

    Need help with tire choice!!

    MICHELIN MS3 work awesome on my boys 05 125 we run Budds-Southfork-VMP
  16. My boy has a 05 yz125 we bought the bike with about 20 hours on it, the previous owner was a friend and he got pretty good and hurt on it. My son is 112lbs soaking wet, i figure 125? with equipment he is a intermediate rider. he has really complained about how this bike beats him to death in the breaking bumps and little stuff,it is obvious when watching him, he loves the suspension over jumps and everywhere else.he claims his kx85 and kx100 handle the breaking bumps/little stuff better than the yz! tried working with the compression and rebound clickers and never seemed to get it any better. I installed softer FACT/CONN springs, he LOVED the way it landed off jumps ect, but it still beat him up over breaking bumps and small stuff. We have tried different oil levels , no help. I have noticed something i feel is very odd the front forks have about 3-3and a hlf inches of sag , under the bikes weight this cant be normal??? We went back to oem springs thinking maybe the others were 2 soft ? Same issue about 3 inches free sag forks have new bushings and seals 5weight amsoil fluid. when i had the base valve out cleaning ect there was about 1-2 inches of slack with the base valve spring. is this normal?? I am sorta lost here !! Thanks in advance
  17. sx455

    yz 125

    I just bought my 13 yo 5'3" 113lb son a 05 last friday. We set the sag and he can stradle the bike and get his tiptoes on tyhe ground. He has no problems riding or racing it . We do need to get it resprung for his wieght, the little stuff (braking bumps ect) are beating him up .
  18. sx455

    KX100 transmission oil????

    We have used the amsoil 10w-40 mc oil and the belray gearsaver ANY of the brandname stuff is a good bet. Find what you can get the best deal on, the secret is change often!!
  19. sx455

    KTM 50 vs Cobra 50???

    Polini makes a good mini also. One of my best friends boy has been riding Polinis for several years, he has had substancially less issues than i have with the KTM. I will be absolutley estatic when my boy gets of the 50s. He has a 50prosenior, that is the highest maintainence POS i HAVE EVER OWNED!!!! All the 50 race bikes are just that, race bikes.Our problem is we ride,ALOT, the KTM is ALWAYS in either broke or getting ready to break.
  20. Could the whole thing be an AMA marketing ploy??? Ricky wins---its business as usual. Bubba wins --- all the major media grabs onto this "the first afro american blah blah " ricky makes all the mx mags ::: Bubba makes People and Rolling Stone and ec ect ect AMA is struggling to become "mainstream" , what better marketing strategy??? You know AMA has "wet dreams" about being like Nascar.
  21. This may be a crazy post to some, but i need alittle insight here from someone with engine experience. I am preparing to put a "big bore kit" on one of my sons bikes. We are getting the bike ready for the supermini class, which allows 105cc. We have both kx100 and kx85 bikes, we of course will be using the kx100 chassis due to larger wheels and longer swingarm. Do we use the kx100 pipe and cdi box,or the kx85 pipe and cdi box? The kx has "milder" cdi box (ignition mapping ect) The pipe also has a different config than the 100, it is quite noticeable when the 2 are compared side by side. SO, which setup should we use? The 85 box and pipe or the 100 box and pipe or maybe even the 100 pipe and 85 box?? Thanks
  22. sx455

    will a kx 100 work for me?

    The kx-100 is about 2 inches taller than a 85. That being said, if you are 6ft 2, you will look like a circus clown on a 100 I moved my 14yo onto a 250f because he looked so out of proportion on his kx100, that was with a raised seat and 2" risers on the bars! He had probs banging his kness on the triple clamps ect he was only 5ft11 How about a kdx200/220?? That can take on a mx track, and the trails .
  23. sx455

    Is a KX65 a good choice for a 7 year old?

    VERY good bike . might take a bit to get used to the "hit", but he's young he will adapt!
  24. sx455

    is a 2000 kx100 frame the same as a 2001?

    Us kx guys are still waiting on that 2nd radiator!
  25. sx455

    Powering down a KX??

    You will probably get more out of the flywheel weight as far as "taming" it down. The bigger fron/or smaller rear will help also and be less expensive,but the "hit" is still gonna be there,just further into the throttle. You could retard the timing one mark ??