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About MountainDog

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    TT Bronze Member

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    Bikes and Guitars
  1. MountainDog

    01 Rm250 owner

    Do you know how well the previous owner maintained it? I mention this as I had an '01 also, and there was a metalurgy thing (improper heat treating) with 3rd gear where the engagement dogs would break. I was real lazy in changing the tranny oil, which contributed to more wear and the blown 3rd gear cost me a $1500 rebuild. So change the tranny oil often, and use an oil specifically for two stroke trannys. Yamalube Trans Oil Plus is a good oil. Has a chemical in it to help harden the gears: http://www.yamaha-motor.com/sport/apparel/apscitemdetail/3/122/all/1/1579/detail.aspx
  2. MountainDog

    RMZ 450 Cranks locking up

    Suzuki Synthetic racing 15W-50: http://www.suzukicycles.com/Accessories/detail.aspx?modelId=a697f811-2bc3-4ade-ae6f-3dea7c78113c&accessoryCategoryId=21f82a97-3f93-4fe3-a9c4-e348af1c82a4&accessoryId=2cb01416-2ad6-47fe-a540-d3cf19e51807
  3. MountainDog

    RMZ 450 Cranks locking up

    I don't think so....click the links: http://www.ronayers.com/fiche/300_0375/crankshaft/crankshaft.bmp http://www.ronayers.com/fiche/300_0375/crankshaft/crankshaft.cfm?man=su&groupid=11250&parent=11240
  4. MountainDog

    RMZ 450 Cranks locking up

    Do you even bother to read any of the posts before spitting out your stupid comments? Did you notice what I wrote?: "I routinely changed oil & filter every 4 hours, used best synthetic oil, kept air filter clean"
  5. MountainDog

    RMZ 450 Cranks locking up

    Attached is a thread about the crank issues: http://www.thumpertalk.com/forum/showthread.php?t=467626&page=2 I posted on 2/13/07 that mine went out and I took to the shop. I just got the bike back 4/10/07 from the shop, $1392.00 later. My crankpin looks worn in the center like the pics in the thread above. The needle cage stayed intact, but with the metal coming off the crankpin, both oil pumps were damaged, the piston skirt scuffed to hell, cylinder scuffed, etc. I had just done a top end about a month before ($600), so none of the $1392 in parts/labor included any head related parts. Since a new cylinder costs $500 from suzuki, my shop instead had it re-electroplated at a place that many race shops take theirs too as it's better than factory, only charged me their $200 cost. We put the ProX rod/crankpin/bearing kit in it as it's better materials than stock. I'm definitely convinced that there is a metallurgy issue with the crankpins (mine was one of the first '05s by the way if that means anything). I routinely changed oil & filter every 4 hours, used best synthetic oil, kept air filter clean, only rode MX practice. I didn't do anything on my own to cause this failure. To support those here that say this is an issue that only happens once in a while, the local mechanic said it's the first he's seen in his shop with the crank issue. I asked him about the Prox and he said I won't have any problems. I then asked him how many hours before I have him tear down and install new crankpin bearing and he said 'at the 4th top end' and he was recommending a top end at 20 hours, so that would be 80 hours. Labor for complete motor teardown to get to that crank bearing is about $500. Fortunately I kept my '04 RM250, so I had something to ride for the last 2 months. Oh....and by the way....on my 1997 RM250, 1999 RM250, 2001 RM250 and the current bike, I've never had to worry about or change the crank bearing/crank pin. I did have 3rd gear transmission blow ups on the 1999 and 2001 due to what became commonly known as bad heat treating of 3rd gear. Bottom line: Suzuki has had demonstrated heat treating issues of parts in the past. No matter how much people here say the people with crankpin failures are 'whiners', you can't escape the fact that there ARE documented crankpin failures in the RM-Z450, even with owner's doing proper maintenance. It seems to occur around 50-60 hours when it does. Looking for magnetic chips in the oil filter along with the 'motor making more rattling noise' sounds like good determinate signs to rebuild the motor as mentioned earlier. The RM-Z450 looks great all fixed and shiny and clean....it's now in the back of the garage with a cover over it. I'm having fun on the two-stroke with about the same lap times.....maybe I never start the RM-Z450 and wait and see what the '08 RM-Z450 offers...then sell the '05 as 'freshly rebuilt engine, so fresh the new owner can do the break-in'.
  6. MountainDog

    What to get when it goes??

    My mechanic said he was getting this for my '05 which is now in the shop for the big connecting rod bearing going out (also took out my cylinder): http://www.pro-x.com/images/nw_connrod.jpg "PROX Connecting Rod Kits are made out of the toughest alloys available today. O.E. specifications and tolerances are meticulously maintained, a guarantee for easy installation and trouble free performance. PROX Connecting rod kit consists of connecting rod, small end bearing, big end bearing,big end pin and thrustwashers." He also said he was getting the Athena piston as it has better scuff resistance. The Prox kit and athena piston were $292.
  7. MountainDog

    connecting rod is OUR culprit

    Got the news, the Connecting Rod bearing breakage took out the cylinder ($500). They suggested also going with an Athena piston as it has better scuff resistance. The Athena piston and the ProX rod kit are $292. Add in $250 of other OEM items (bearings/seals/etc for the rebuild) and $400 labor, I'm looking at $1500 with tax. The bummer is that a top end (piston, rings, valve seals, timing chain, springs, gaskets, etc) was $600 with labor. Let's say you need to do that every 50 hours. From what I've read here, the Connecting Rod bearing is only good for 60+ hours. So that means you should do top end and connecting rod bearing every 50 hours. Take the top end $600, add another $250-$300 labor for removing engine and complete tear down & crank unpress/repress, + $50 lower con rod bearing & tax and this all adds up to $1000 of maintenance every 50 hours. If I ride MX practice for 2 hours a weekend, then every 6 months I'll have to spend $1000, or almost double than a top end just because of a poor quality bearing and/or bad oil supply to the bearing design. Hopefully the ProX bearing is better materials so maybe I can go 100 hours for every crank/rod bearing rebuild. Good thing I still have my 2004 RM250 in the garage.
  8. MountainDog

    will carmichael be racing indy in '07

    Without Carmichael, the Supercross' aren't too exicting. Couple that with the new rules of qualifying by practice lap times (eliminating qualifiers) and the elimination of the Semi races makes for a more boring day at the races as you see less official racing. I went to A1, A2, A3 this year (along with the past years). I won't be doing that next year!
  9. MountainDog

    will carmichael be racing indy in '07

    This is RC's 2007 schedule (no Indy): http://supercrossonline.com/rc
  10. MountainDog

    connecting rod is OUR culprit

    That describes exactly what I noticed. Mine was still running strong (with the loud clanking) when I stopped riding it. Still awaiting the phone call from the mechanic as to what other internal parts are damaged, but at least it didn't blow or seize. I think this is the rebuild kit he was talking about using: http://www.pro-x.com/images/nw_connrod.jpg "PROX Connecting Rod Kits are made out of the toughest alloys available today. O.E. specifications and tolerances are meticulously maintained, a guarantee for easy installation and trouble free performance. PROX Connecting rod kit consists of connecting rod, small end bearing, big end bearing,big end pin and thrustwashers."
  11. MountainDog

    connecting rod is OUR culprit

    I saw this thread last week. My '05 RM-Z450 has been making more noise after full top end rebuild a couple months ago, so I wondered about this crank bearing issue. This past weekend, it started making a very loud clunking from around the lower end. Bike still ran strong. Took to shop and got the call today that it looks like the crank bearing going bad on mine. The mechanic mentioned an aftermarket crank rebuild company that uses better bearings than original (I think he said Pro-X), so I hope that cures it for the future. Does anyone know if this is related to '05s only? Did they upgrade the bearing for '06/'07?
  12. MountainDog

    Just switched to 2 strokes

    I have an '04 RM250 and my son has an '05 RM250. As recommended, change the tranny oil often. Yamaha Trans Oil Plus is a great affordable trans oil. Has anti shear and other additives to withstand temp and gear pressures: http://www.yamaha-motor.com/sport/apparel/apscitemdetail/3/122/all/1/1579/detail.aspx As far as pre-mix, Yamalube 2-R is a semi-synthetic and has great results as the guy on the linked thread mentions. Suzuki recommends 30:1 and that's what we run with no problem, no fouling plugs, no drool, no excessive smoke with the 2-R: http://www.yamaha-motor.com/sport/apparel/apscitemdetail/3/121/all/1/1424/detail.aspx The only change we did to the '05 is go up one tooth on the rear sprocket and a Pro Circuit pipe (stock silencer).
  13. MountainDog

    What Size Tyres

    I just went thru a big frustration on tire sizes. When my original equipment Bridgestone 402A 120/80-19 wore out a long time ago, I wanted to go with my favorite Dunlop 756, so I told the local shop to order one "in that new larger RM-Z450 size". They looked on line at Suzuki's website and saw 120/90-19 and looked in their Parts Unlimited catalog and saw 120/90-19, so that's what they ordered and that's what I got. (Yes, stupid me didn't bother to look at the size of the tire on my rim). Fast forward to a couple weeks ago when I needed a new Dunlop 756. I looked at my bike's tire, saw 120/90-19 and called around a few shops and found a Kawasaki dealer that had one. Took my wheel in and the guy said 'what bike's that for', so I told him, and he told me "yours came with a 120/80-19, which we have in stock, also look at the back of the KX450F over there, the Dunlop 756 in that size comes stock", and showed me his Bridgestone parts book. I then called my son who has stock original tire, and yep, 120/80, looked in the owner's manual, yep, 120/80, looked at the RM-Z450's at the Suzuki exhibit at Anaheim supercross, yep 120/80. Looked at Bridgestone's website, yep 120/80......Looked at Suzuki's website, they show WRONG 120/90 for '07, '06, '05. Sunday I rode MX practice with the 120/80, felt like a completely different and much improved bike, cornered much much better than the 120/90. The 120/80 is lighter than the 120/90 so it flicks side to side easier and it can 'rev up' quicker. I was so pissed to find out I was running the wrong tire for months and months just because of a couple website errors and my failure to look at the original tire!
  14. MountainDog

    Is a 99 RM250 good?

    32:1 ratio gas/oil. I use/recommend Yamalube 2-R For tranny oil, I use/recommend Yamaha Trans Oil Plus I had a '99. Change the tranny oil often (like once a month) and you won't have any gear issues. I neglected my oil changes and blew 3rd gear. You might wonder why I use Yamaha oils. My local Yamaha/Suzuki dealer had a parts guy that rode RMs (got one every year). When I told him of my tranny problem, he took me over to the Yamaha oil rack and put like 4 of the Trans Oil Plus bottles in my arms and said change it every other ride and you'll never have any tranny problems. I've done that on my '04, but most people would say that's excessive, so that's why I said every month. At like $5 a bottle, that's cheap insurance.
  15. MountainDog

    What's the deal with my RM??

    The microfiche for 1993 shows Item# 14 as 36x52x7 and Item #15 as 20x37x6. I'm guessing the 36 is mm for inner diameter. You mention putting in a 38x52. If so, and if that means 2mm larger, then that seal is probably not sealing on the crank correctly and letting tranny oil inside. http://www.ronayers.com/fiche/300_0254/crankshaft_1993/crankshaft_1993.cfm?man=su&groupid=10840&parent=10640