why dont they make them anymore?

[schmanman]

it's as simple as that.

why dont they make 175 cc bikes anymore? It's a good size.
I know there are 150's, but from what I understand, they are a little lacking in the oomph department.

oh, and why dont they make rotary valve 2-strokes?
I have one, takes off like a 4-stroke, puts out excellent power, starts easy, and doesn't require you to replace reeds.

what is the average horsepower of a 125cc 2-stroke, and 4-stroke.
a 250cc?

thanks guys. you know a bunch more than me, I'm just curious. :)

 

[just_a_rider]

I don't know but I have rode a 175cc 2 stroke bike back in the 80's, I think it would be a perfect match for those 250f's.

 

[schmanman]

what do you mean? my bike would be like a 250 f?

 

[just_a_rider]

Exactly, the bike was sweet, it was a Yamaha enduro 175, a 85 model I think. I would have bout it but didn't have the funds as I was a young man with a 5 buck an hour job with a car payment :|

 

[schmanman]

ohh, mine has similar power figures.
cool! I'm happy!

I'm just curious about my above questions, and if I can figure out how powerful my bike is compared to some modern one, that's great!

thanks!

 

[BadgerMan]

A good running 70's vintage 175cc "enduro" produced about 15hp. A modern day 250F produces more than twice that amount.

Back in the seventies, a good running 125 mx'er made about 20 hp. Now they are producing over 30hp.

The 1976 KD175 I owned (in 1976) was a ball to ride but it was no match for any of the 125 motocrossers that I came up against. After getting tired of continually eating roost from my friends and their 125's, I traded up to a 1979 Montesa 250 Cappra. My roost eating days were over! :laugh:

Just enjoy the KE175 for what it is......a nice reliable and fun bike from a better time.

 

[schmanman]

mine produced 17 hp new, had a little better than stock compression, and has a preformance pipe... so I think it could be making 20 hp.
maby more, if I'm real lucky

how much do aftermarket exhausts help the horsepower?

It is a ball, especially for free. I just got a new set of tires.
look a little farther down in the thread in the link.

http://dirtrider.net/forums3/showthread.php?t=147854

wow, I'm just full of questions today. :whoa:

 

[BadgerMan]

I put a Wirges pipe (just like yours) on my KD175. It added one or two hp......based on my seat of the pants estimate.

 

[schmanman]

oh! yeah....

your probably the one who told me about the pipe being a preformance in the first place. *embarrassed*

do you think I chose good tires? I went off what the people on this forum, and the place said.

 

[pryor]

I have the same tires on my CZ, havent had them long but they seem to work good. :cool:

 

[Britt Boyette]

I think they went away because the FIM or whomever allowed a displacement bump up to 200cc's for enduro racing. That's why there were KDX200's and IT200's etc... for the longest time. KTM still has the 200SX and Kawasaki had the KDX200/220 which was discontinued after 2006.
You may want to actually ride a modern 250F before you compare the KE/KD175 to it. There is a huge HP/torque difference in favor of the 250F.

 

[2 strokes for life]

IT175 can beat a CRF450R at its vere topend power but none the less i can do it. It may only have 15HP but it is a blast to ride. P.S. it eats 250Fs for lunch

 

[schmanman]

cool. I have been riding all over the place since I have the day off, and I love them!

good grip on muddy ground, but on hard pack and everything else too.

of course, my old tires might as well have been slicks, they had an 1/8 inch of rounded off rubber knobs. they were 70's dual sport/trials tires.

how much did it cost you?
with installation, new tubes, etc, it was $240 bucks for me.
is that a fair price?

well, I know it's a blast to ride, and does not require much maintenance.
I love it.

and I get it, I could get my butt whipped by a modern 250.
oh well, I'm not gonna be racing anyway.

 

[BadgerMan]

IT175 can beat a CRF450R at its vere topend power but none the less i can do it. It may only have 15HP but it is a blast to ride. P.S. it eats 250Fs for lunch

Your bikes must gain some HP and MPH when converting to the metric system.

;)

 

[2 strokes for life]

I am not kidding. Once we pass 70 or so mph i pass him.

I got my bike for $900 with new tires. It was a rip off but i am rebuilding at the moment and soon should be far more cabable of a trail bike. The IT465 is also anothe favorite of mine. The bottom end on it is crazy good.

 

[schmanman]

i like the powerband on my ke. nice and smooth. actually, there is not much of a power band, it is really good at the top and bottom.

oh, here's some pics with my new tires!
well well worth the $245.00.
they are 1000% better in the mud, dirt, and grass than my old ones. the offroad performance with them is phenomenal compared to the old tires. I can handle everything but jumps, since the suspension travel is....uh.... not the best, to put it one way, although it does help smooth things out considerably.

the old tires, in my workshop...

front...

rear...

look at how much less tread, and less aggressive tread there is on those old ones! those old tires are crap!

 

[Britt Boyette]

IT175 can beat a CRF450R at its vere topend power but none the less i can do it. It may only have 15HP but it is a blast to ride. P.S. it eats 250Fs for lunch

Thanks for the chuckle! I laughed so hard I almost pissed myself! :rotfl:

 

[2 strokes for life]

My bike has the 2nd or 3rd over bore, porting, reeds, aftermarket pipe, and FMF turbine core. This thing kicks. It has no bottom end hardly but the top end power is awsome.

Well, this spring i will get it on tape beating a 2002 YZ250, 1986 RM250, 2001 YZ125, and the CRF450R i will have to wait for because he is not arround here anyother time but summer.

 

[katoom 300 rider]

Exactly, the bike was sweet, it was a Yamaha enduro 175, a 85 model I think. I would have bout it but didn't have the funds as I was a young man with a 5 buck an hour job with a car payment :|

I had a Yamaha DT or IT175 about 12 years ago, I bought it off a Farmer who just putted around the fields with it, what a nice little bike, not a lot of power, but it went up any hill you pointed it at.
I beat, I mean I rode that bike for a couple of years, and bought a KDX200.

 

[earl pittz]

Are rotery valve bikes any quieter?

 

[schmanman]

while idling, maby, but at WOT, this thing is louder than any modern 2-stroke. probably because they did'nt really have db limits then. the bike has no silencer. maby the stock exhaust was quieter. I have no idea. :whoa:

 

[CommandoRoadster]

Schmanman-
Glad to see you lived through your old tires,and are enjoying your new ones! :nod: (I think you should get those old tires bronzed,and hang 'em on the wall ,with a sign that says something like "Ah,the folly of youth....") What air pressure are you running? Do you ride at night? If not,ditch the headlight.It will make the front end, and steering, feel a lot lighter. Nighttime trailriding can be a lot of fun though. Just stick to familiar trails.

On a smooth surface,in a straight line,you just might surprise someone on a 4 stroke MX bike. :cool: Especially if the other rider didn't know how to keep his engine on the boil. At least,you would not be badly embarrassed. Your bike may not have as much max torque,or horsepower,but it's got a lot quicker power delivery,with a harder midrange hit. Those old Kawi 2 smokers sure feel quicker,that's for sure! :)

Two Strokes for life-
Your bike must have roadrace porting,and gearing,thats all I can say! :laugh:

Earl-
Rotary valves work on the intake side of the engine,so have no effect on the exhaust note.

Schmanman-
Rotary valve engines are no longer produced, because reed valve tech advanced to the point that reeds have most of the advantages of rotary valves with none of the drawbacks.I think I explained it in more detail,on my post on your other thread. If not,let me know,and I will try to be more specific.
:p
Cheers!
Bruce

 

[CommandoRoadster]

Oh, and for the gods sake,please,get a silencer! :yikes:

 

[schmanman]

Schmanman-
Glad to see you lived through your old tires,and are enjoying your new ones! :nod: (I think you should get those old tires bronzed,and hang 'em on the wall ,with a sign that says something like "Ah,the folly of youth....") What air pressure are you running? Do you ride at night? If not,ditch the headlight.It will make the front end, and steering, feel a lot lighter. Nighttime trailriding can be a lot of fun though. Just stick to familiar trails.

On a smooth surface,in a straight line,you just might surprise someone on a 4 stroke MX bike. :cool: Especially if the other rider didn't know how to keep his engine on the boil. At least,you would not be badly embarrassed. Your bike may not have as much max torque,or horsepower,but it's got a lot quicker power delivery,with a harder midrange hit. Those old Kawi 2 smokers sure feel quicker,that's for sure! :)

Two Strokes for life-
Your bike must have roadrace porting,and gearing,thats all I can say! :laugh:

Earl-
Rotary valves work on the intake side of the engine,so have no effect on the exhaust note.

Schmanman-
Rotary valve engines are no longer produced, because reed valve tech advanced to the point that reeds have most of the advantages of rotary valves with none of the drawbacks.I think I explained it in more detail,on my post on your other thread. If not,let me know,and I will try to be more specific.
:p
Cheers!
Bruce

thanks that clears everything up!


ok, I will try to get a silencer, although I doubt any are made that fit.

 

[2 strokes for life]

Could you imagine a new liquid cooled WR175 2 stroke. I would buy it in a heart beat.