ktm sx 105 2 stroke

[willmx11]

can i get some reviews on this bike? id like to know how it handles the power. and the maintence do they foul plugs easily and how often you need to replace the top end on them or do they blow easily. i was also wonderin how they compare to honda crf 150f's. thats what i have now. i was wonderin if there faster and if they have more torc. every tip helps. thanks

 

[note]

can i get some reviews on this bike? id like to know how it handles the power. and the maintence do they foul plugs easily and how often you need to replace the top end on them or do they blow easily. i was also wonderin how they compare to honda crf 150f's. thats what i have now. i was wonderin if there faster and if they have more torc. every tip helps. thanks

they are lighter than the 150r. the have simaler power. realy its just 2 stroke vs four. what kind of riding do you do?

 

[Slamnek]

Talk to Ladydirt on here she has one and really seems to like it.

 

[-LadyDirt-]

My bike is a 105, and they're pretty rare. They are a step up from an 85 cc, and in between a 85 and 125.. a lot more bottom end power and torquey little bastards. I LOVE this bike. The KX 100 is very similar too. The size and brand of bike doesn't depict how often you need to do a top end, its how hard you ride it. Fouling plugs also has nothign to do with the size of the bike it has to do with, again..how hard you ride it and how rich you mix your oil/gas ratio. I mix my bike rich after I do a top end then lean it out after otherwise I will foul plugs constantly because I don't romp on my bike enough (these bikes are meant to be raced... not puttsin..) However with some good oil your usually pretty safe around 50:1 oil/gas ratio. This bike is nothing in comparison to your crf150, you have the crf150f right? Ya..this is a trail bike... like i've told you before a 2 stroke is a completely different beast. And like we've said earlier... your going to outgrow a 100 or 105 in a season tops.. that and... good luck finding a 105 for less than 4g... I'll sell ya mine for $4200 if you really want one that bad I want to upgrade to an XC

 

[-LadyDirt-]

Feel free to ask me more questions if you like, I'm pretty sure i'm the only person on this site who owns a 105, but dude I honestly think your going to outgrow this bike way too fast... sure its a good beginner bike to learn on but for the amount your going to pay, it's almost not worth it..you could easily find a nice 125 for under $3000..KTM's are expensive, and parts are double compared to japanese bikes. For example, YZ 125 clutch - $14. KTM 105 clutch - $40.. but if you really insist I'd suggest looking at a KX100 ...tons of them for sale and cheaper to maintain... just sayin.

 

[Modman]

You shouldn't ever foul a plug on a bike that is tuned right. If you are fouling plugs on say 50:1, then your air/fuel is way too rich. You can either lean it out on the air/fuel or run a hotter plug. I run my sleds at 32:1 oil ratio and one range hotter on the plugs and I've never had a problem.

Hope that helps.

 

[-LadyDirt-]

Yeah i've got a better plug in now and leaned my bike out now that the motor is broken in, and she's not fouling anymore. I fouled my plug twice this season just becuase I was mixing way too rich and had an old chitty plug in there, KTM 13-44 got my baby runnin like a top! And i'm runnin 50:1 rather then like 32:1 Never fouled a plug in my Yamaha, and I ran it 50:1 all the time. I just don't ride a bike hard enough to mix it rich I guess haha

 

[willjeffwilljeff]

Yeah i've got a better plug in now and leaned my bike out now that the motor is broken in, and she's not fouling anymore. I fouled my plug twice this season just becuase I was mixing way too rich and had an old chitty plug in there, KTM 13-44 got my baby runnin like a top! And i'm runnin 50:1 rather then like 32:1 Never fouled a plug in my Yamaha, and I ran it 50:1 all the time. I just don't ride a bike hard enough to mix it rich I guess haha

Many dirt bikers are mixing their gas at ratios as high as 75 to l, or even 100 to 1 with the new generation oils, in the belief that their bike will put out the most horsepower at a higher ratio. Riders who foul plugs all the time, are put ting less oil in their gas/oil mix, in the belief that the oil is fouling the plugs, and many racers are trying to solve “too rich, too lean” problems by changing the gas/oil mix in stead of the jetting.

 

[-LadyDirt-]

Many dirt bikers are mixing their gas at ratios as high as 75 to l, or even 100 to 1 with the new generation oils, in the belief that their bike will put out the most horsepower at a higher ratio. Riders who foul plugs all the time, are put ting less oil in their gas/oil mix, in the belief that the oil is fouling the plugs, and many racers are trying to solve “too rich, too lean” problems by changing the gas/oil mix in stead of the jetting.

Yeah jetting is a problem too, but my mechanic had my bike jetted last season after the motor was rebuilt so that I could run it rich while breaking it in, but until I get the jetting re-done, leaning it out is helping, as when it is mixed too rich the plug fouls easily, especially if i'm not giving it hard enough.. but when i'm on the throttle constanly, climbing hills, etc I dont have problems with fouling plugs, but thanks for reminding me my mechanic is coming to pick my baby up tonigh ti'll have to remind him to re do the jetting!

 

[willjeffwilljeff]

If you do foul plugs, it is more than likely caused by poor jetting, not a bit too much oil. If you get your bike jetted correctly, have a fresh plug and a strong ignition system, you won’t foul plugs.

When the motor is idling, or at lower rpms, that’s when the machine has a greater chance of fouling a plug. Minibikes and 125s have even less chance of fouling plugs, because they are ridden at such high rpm. Because of the ultra high rpm, the load on a given part is much higher on a 125, than on an Open bike.

Plugs should not foul at richer ratios if you are using high-quality oil in the mix. High-quality oils will have a good detergent/dispersing package that holds down the contaminants which produce plug fouling.

A typical example: you go from a 50:1 ratio to a 20:1 ratio. Your engine will now run leaner, and you’ll have to make jetting changes. You’ll need bigger (in number) jets because the oil molecules are thicker and the flow rate (the amount coming through the jet) is less.

Aha! The volume of fuel has changed. The oil takes up some volume that the gas used to occupy, so your engine is getting less gas and needs to be richened up.

 

[-LadyDirt-]

If you do foul plugs, it is more than likely caused by poor jetting, not a bit too much oil. If you get your bike jetted correctly, have a fresh plug and a strong ignition system, you won’t foul plugs.

When the motor is idling, or at lower rpms, that’s when the machine has a greater chance of fouling a plug. Minibikes and 125s have even less chance of fouling plugs, because they are ridden at such high rpm. Because of the ultra high rpm, the load on a given part is much higher on a 125, than on an Open bike.

Plugs should not foul at richer ratios if you are using high-quality oil in the mix. High-quality oils will have a good detergent/dispersing package that holds down the contaminants which produce plug fouling.

A typical example: you go from a 50:1 ratio to a 20:1 ratio. Your engine will now run leaner, and you’ll have to make jetting changes. You’ll need bigger (in number) jets because the oil molecules are thicker and the flow rate (the amount coming through the jet) is less.

Aha! The volume of fuel has changed. The oil takes up some volume that the gas used to occupy, so your engine is getting less gas and needs to be richened up.

haha see this why I have a mechanic work on my bike, he tells me this stuff and really as much as I try to pay attention, I just pay attention to my bike and how it is reacting. He jetted my bike just fine last season it didn't foul a single plug until this season (and yeah..its only happened when it was idling) He hasn't looked at my bike since last season so guarantee he'll get it tuned up. Dont worry, this guy know's his chit.. been racing and working on motorcycles for 20 or so years, and works on my bike on the side so its a good deal. I think I had a really chitty plug in there too, cuz as soon as I changed it out to a newer one..it's been running fine and hasn't fouled yet. Hmm I guess we'll see!

 

[willmx11]

My bike is a 105, and they're pretty rare. They are a step up from an 85 cc, and in between a 85 and 125.. a lot more bottom end power and torquey little bastards. I LOVE this bike. The KX 100 is very similar too. The size and brand of bike doesn't depict how often you need to do a top end, its how hard you ride it. Fouling plugs also has nothign to do with the size of the bike it has to do with, again..how hard you ride it and how rich you mix your oil/gas ratio. I mix my bike rich after I do a top end then lean it out after otherwise I will foul plugs constantly because I don't romp on my bike enough (these bikes are meant to be raced... not puttsin..) However with some good oil your usually pretty safe around 50:1 oil/gas ratio. This bike is nothing in comparison to your crf150, you have the crf150f right? Ya..this is a trail bike... like i've told you before a 2 stroke is a completely different beast. And like we've said earlier... your going to outgrow a 100 or 105 in a season tops.. that and... good luck finding a 105 for less than 4g... I'll sell ya mine for $4200 if you really want one that bad I want to upgrade to an XC

what year is yours and how long have you had it? i can always bore it out if i need to when i out grow it. i prolly wouldnt have it very long anyways. its either this bike or the honda crf150r so which one would you suggest?

 

[willjeffwilljeff]

Knowledge is power

 

[willjeffwilljeff]

My wife had 2007 105, and the thing about 105 is it's a real bike .It's race ready with the same quality of parts as there big bike (adjustments and longevity). The bike has more then enough power to walk all over CRF150R(which is made to race in the 85 class) for the same money. Plus 2-stroke are more fun.
Its for riders too tall for 85cc machines but too short or light for 125, 200 or small-bore four-strokes. Is it right for you?

 

[willmx11]

My wife had 2007 105, and the thing about 105 is it's a real bike .It's race ready with the same quality of parts as there big bike (adjustments and longevity). The bike has more then enough power to walk all over CRF150R(which is made to race in the 85 class) for the same money. Plus 2-stroke are more fun.
Its for riders too tall for 85cc machines but too short or light for 125, 200 or small-bore four-strokes. Is it right for you?

well ya 85s are to small and 125s and 250s are still to big. so i think it would be right. but there pretty hard to find right now, i went to a ktm dealer today and even they coulddnt find one and they done have left. but there gonna look for me a couple weeks and if they still cant find one then ill go with the 150r prolly.

 

[-LadyDirt-]

Knowledge is power

You're very right, and I am still learning, and thats why I ask a lot of questions..I want to learn as much as I can about bikes because the more you know the better off you are!

 

[Thunderr]

Here you go.

Calgary ktm classifieds, find ktm in Calgary - Kijiji Calgary Free Classifieds

 

[-LadyDirt-]

what year is yours and how long have you had it? i can always bore it out if i need to when i out grow it. i prolly wouldnt have it very long anyways. its either this bike or the honda crf150r so which one would you suggest?

Mines a 2006. I've had it for ..9 months? And I am the 2nd owner. I have redone everything to this bike, complete brand new top/bottem end engine with maybe 20 hrs on it?, new brakes, forks, tires, and soon a new pipe. It's an amazing bike, and would no doubt kick the chit out of a 150r. Just depends if you want to go 2 stroke or 4 stroke but yes, I agree with WillJeff.. 2 strokes way more fun. It would be very hard for me to let this bike go, so the price would have to be right, and so far, its got over 4g into it. Mine keeps up to 125's my mechanic races 450's, and he even says that my bike scares him..but he's got it running pretty good. I am almost willing to bet that you would not find a decent KTM 105 for under 4g..and if you do..its likely because something is going wrong with it and your gonna have to dump money into it soon enough.. just sayin. BUT.. you could always look at KX 100's.... if you want something cheaper.

 

[-LadyDirt-]

Here you go.

Calgary ktm classifieds, find ktm in Calgary - Kijiji Calgary Free Classifieds

haha..I've had my eye on that XC for like 5 months now.. it hasnt' sold yet. I'm surprised he reposted it for 5g, cuz the last day I looked in the Edmonton section he had it for 4800 or 4900..

 

[Modman]

haha see this why I have a mechanic work on my bike, he tells me this stuff and really as much as I try to pay attention, I just pay attention to my bike and how it is reacting. He jetted my bike just fine last season it didn't foul a single plug until this season (and yeah..its only happened when it was idling) He hasn't looked at my bike since last season so guarantee he'll get it tuned up. Dont worry, this guy know's his chit.. been racing and working on motorcycles for 20 or so years, and works on my bike on the side so its a good deal. I think I had a really chitty plug in there too, cuz as soon as I changed it out to a newer one..it's been running fine and hasn't fouled yet. Hmm I guess we'll see!

Before any rider (or racer) starts monekying with jetting or the gas/oil ratio - they should do a plug check. Knowing what is causing the plug to foul will allow you to determine what the fix for the fouling plugs is - too much oil or jetting. I'm always hesitant to cut back on the oil ratio, a standard 2 stroke ratio for anything from race bikes to weedeaters and chainsaws is about 40:1. Anything in the 30:1 to 50:1 range is fine IMO, but I would never go higher than 50:1 in any 2 stroke I own.

Not running enough oil will toast your motor and leaning down your bike because it is fouling plugs at idle is not a good idea unless they are certain it's the idle fuel circuit and not the main fuel circuit. Give your bike as much oil as it will take without fouling plugs when jetted correctly IMO. I have over 3000 kms on my one sled motor, popped the head off and measured the bores this year, new clearance on the pistons to the bore was 0.0039", I'm at 0.0040". Wear limit is 0.0048". Virtually no wear after 3000 kms and I use a regular everyday oil (Shell Advance regular - not the synthetic), not a fancy oil. Its about how much you use - not the type IMO. People who skimp out on oil typically wind up with motors as expensive paperweights. A well oiled motor is a happy motor.