dirt bike questions

dirtfan21 · November 8, 2012

My hang up on 4-strokes has always been the added weight and also the added cost of a rebuild. I had an '03 KTM 250sx which was the craziest thing I have ever been on. Actually, I sold it to my buddy who had a modded out Kawi 450 who couldn't understand how I killed him until I ran out of gear in 5th. I also have a buddy who races a YZF 450 and he couldn't believe my KTM.

The only point I'm going to make is with a 2 stroke there is less weight, less maintenace, easier rebuild, and cheaper rebuild. This is coming from a guy who had a modded YFZ 450 that ate up modded Banshee's, well not ALL of them, some guys are nuts with their bikes. I loved that quad but it terrified me to spend the money to rebuild it if I blew it up, and checking valves often was a total pain in the ass.

As for sleds, I'll take a Ski-Doo 800 over a turbo 4-stroke anyday. That is just my opinon.

HEMICAT · November 8, 2012

As for sleds, I'll take a Ski-Doo 800 over a turbo 4-stroke anyday. That is just my opinon.

Me too! I like to tear around, jump, handle, stand, powder ride, pull up ski's - more than just go fast in a straight line.

The new e-techs I think prove 2-strokes are here to stay and can be as clean, fuel efficent, powerful and still more fun to ride.

Squirrely · November 8, 2012

As for sleds, I'll take a Ski-Doo 800 over a turbo 4-stroke anyday. That is just my opinon.

Me too! I like to tear around, jump, handle, stand, powder ride, pull up ski's - more than just go fast in a straight line.

The new e-techs I think prove 2-strokes are here to stay and can be as clean, fuel efficent, powerful and still more fun to ride.

I hope that tech spills into the moto world.

slimjim2525 · November 9, 2012

My hang up on 4-strokes has always been the added weight and also the added cost of a rebuild. I had an '03 KTM 250sx which was the craziest thing I have ever been on. Actually, I sold it to my buddy who had a modded out Kawi 450 who couldn't understand how I killed him until I ran out of gear in 5th. I also have a buddy who races a YZF 450 and he couldn't believe my KTM.

The only point I'm going to make is with a 2 stroke there is less weight, less maintenace, easier rebuild, and cheaper rebuild. This is coming from a guy who had a modded YFZ 450 that ate up modded Banshee's, well not ALL of them, some guys are nuts with their bikes. I loved that quad but it terrified me to spend the money to rebuild it if I blew it up, and checking valves often was a total pain in the ass.

As for sleds, I'll take a Ski-Doo 800 over a turbo 4-stroke anyday. That is just my opinon.

All valid points no doubt. And all true.

J-man67 · November 16, 2012

As mentioned before...its all about torque. I currently ride a yz-250 and I LOVE it for what I do, which is now just woods single track, a few visits per year to the MX track, and messing around on our property. lb for lb, CC for CC 2-strokes RULE, but its alllll about tractable power. You can have more HP all day long, but if you cant transfer that to the ground, its worthless. 2T have a high rpm hit (which makes me smile just typing about it) and it sure does feel like a rocket...and it is, but a 4 strokes low end grunt and the manner it is applied (slightly more subtle if you will) let the tire get that extra bite, whereas a 2t wants to spin. Its all about power transfer and....torque. At least that is my take on it. In closing...LONG LIVE THE 2 STROKE haha. I dont hate 4 strokes, but when my bike blows up...and they all do, I love being able to drop 200 bucks, 20 of that being on beer, taking a few hours on a weekend and re-doing the top end and then riding that day...if I didnt drink any of said beer :o) I love seeing the arguments from both sides, as both are correct... its mainly preference.

idahojoe · October 19, 2013

Looks like i'm a year late discovering this topic; but curious to know how you like your 03 CRF450? I have one too. For me it was a wild step from my 93XR600!(before that: an awesome 84 XR500)My switch from a used 1976 Honda trials bike to the 84 XR500 was like riding a Cadillac.) My son has a 02 CR250; so we have the best of both worlds (2-stroke 250 vs 4-stroke 450 discussions herein this topic...). I joined "THUMPERTALK" when I got my 03. I learned a lot about my bike from the forum ; much like I came to GM-trucks to get info when I bought my diesel. On my bike, I tilt it until I see the first bit of gas come from the carburetor overflow tube hit the ground. Put the bike straight again. Then get the piston at top dead center. Then kick it like you mean it! On mine; this "tilting" works more consistently than any experimentation with throttle position during starting..... Again; if you still have the CRF450....."THUMPERTALK".com. As others have mentioned; be prepared for annoying overheating, fun with starting as your valves keep needing adjustment; counterbalance wear and replacement; etc.. In spite of all that, I still like it. My son likes mine more than his cr250; but I like to get on his CR, so it works out nicely. By the way, I bought the Kibblewhite steel valve kit to replace the stock titanium valves; and there have been no problems with starting since.

Prokopchuk_9 · October 19, 2013

Looks like i'm a year late discovering this topic; but curious to know how you like your 03 CRF450? I have one too. For me it was a wild step from my 93XR600!(before that: an awesome 84 XR500)My switch from a used 1976 Honda trials bike to the 84 XR500 was like riding a Cadillac.) My son has a 02 CR250; so we have the best of both worlds (2-stroke 250 vs 4-stroke 450 discussions herein this topic...). I joined "THUMPERTALK" when I got my 03. I learned a lot about my bike from the forum ; much like I came to GM-trucks to get info when I bought my diesel. On my bike, I tilt it until I see the first bit of gas come from the carburetor overflow tube hit the ground. Put the bike straight again. Then get the piston at top dead center. Then kick it like you mean it! On mine; this "tilting" works more consistently than any experimentation with throttle position during starting..... Again; if you still have the CRF450....."THUMPERTALK".com. As others have mentioned; be prepared for annoying overheating, fun with starting as your valves keep needing adjustment; counterbalance wear and replacement; etc.. In spite of all that, I still like it. My son likes mine more than his cr250; but I like to get on his CR, so it works out nicely. By the way, I bought the Kibblewhite steel valve kit to replace the stock titanium valves; and there have been no problems with starting since.

It's usually not the valves that's the problem, it's the seats. The seats pound into the head giving you zero clearance on intakes. Kibble whites are good, but did you upgrade the seats too? My buddy runs bigborethumpers.com head with OEM valves and copper beryllium seats has almost 150 hours still has perfect intake clearance

KMGZ400 · October 21, 2013

haha i remember this... i got rid of the CRF, a friend wanted to buy it and i made a good profit. valves needed adjustment when i got rid of it though.

i figured out the hard starting thing too from another friend that had one.

i loved the bike though.. it was decent in stock form and had crazy power. have the itch for another one im in the market for another 450.. preferably a honda

Carder09 · October 21, 2013

haha i remember this... i got rid of the CRF, a friend wanted to buy it and i made a good profit. valves needed adjustment when i got rid of it though.

i figured out the hard starting thing too from another friend that had one.

i loved the bike though.. it was decent in stock form and had crazy power. have the itch for another one im in the market for another 450.. preferably a honda

Check into the KTM market lately? I have been wanting to check out the 300 XC. And to get a look at the 350 XCF-W if I cross over to the 4 stroke world.

KMGZ400 · October 21, 2013

KTM's are awesome and yeah the 350 is what id look at or a 450.. but im sure as you know they are a tad pricey.... people around me want WAY to much for newer clean used ones.. I can get a same year same condition 450 for the price of a used KTM 125 around me.

Prokopchuk_9 · October 21, 2013

KTM's are awesome and yeah the 350 is what id look at or a 450.. but im sure as you know they are a tad pricey.... people around me want WAY to much for newer clean used ones.. I can get a same year same condition 450 for the price of a used KTM 125 around me.

Even after all my argument I still picked up a. 450 too haha, they are fast. But yet again here I am adjusting valves every ten hours already!! Got a really good deal on it, has valves pro -action suspension too. Quick bike. Still love my 250 2t tho!!

04 450 and still got my 2t!!!

Still love the ol two smoker!

KMGZ400 · October 21, 2013

hahaha couldnt resist could ya...i dont mind adjusting valves... although i got about 60-70 hours before my valves had to be adjusted.. stock motor though

Hawk2463 · October 26, 2016

The easiest way to start a big bore four stroke is to Always kick the kick lever slowly down until the engine stops you. At that point you are just before TDC(top dead center) at that point let the kick leaver release all the way to the top and then stand on that puppy all the way down. Raced my two xr's for years. They always cranked on first kick this way regardless cold or hot. It's true that it's best not to touch the throttle. Just choke it when cold. But if started like I said a little throttle hot or cold won't really matter much. Oh yeah, your not a bike rider...when I say stand on it I mean sort of jump up in the air with your right foot on the kick starter and on the way back down put all your weight on the kick starter. Big bores are hard to kick past TDC with or without a compression release. Have fun big bores are a BLAST