Older bikes as fast as the new bikes ?

john3_16

Member
May 17, 2004
808
0
Wow..This is an old thread!!!

I haven't been here for a while and tried to log in several times but failed because I couldn't remember my user name...Started seaching around and decided to look in the 2 stroke forum to see what folks were talking about these days and the thread I started was on the first page and saw the user name and.......It was mine! Helped me to remember....

Yeah..Old thread...84 RM125 is a neat bike but I'm not so sure about 41 HP.....

Anyway reading over the thread many interesting comments....Kind of miss the 80's..Just doesn't seem the same anymore...Seems today the largest difference is in the chassis refinements....
 

whenfoxforks-ruled

Old MX Racer
~SPONSOR~
Oct 19, 2006
8,129
2
Merrillville,Indiana
And that John 3-16 is why I want to put a 82 cr480 motor in an aluminum frame, 125 or 250f. I have a guy for the welding. I have the engines. A guy in Pa has my rolling frame! Vintage Bob
 

john3_16

Member
May 17, 2004
808
0
whenfoxforks-ruled said:
And that John 3-16 is why I want to put a 82 cr480 motor in an aluminum frame, 125 or 250f. I have a guy for the welding. I have the engines. A guy in Pa has my rolling frame! Vintage Bob


Oh wow...Definitely keep us updated on that...Sounds like fun project!
 

cujet

Member
Aug 13, 2000
826
5
Just an FYI, the Honda CR125 based shifter Kart engines dyno (at the wheels) at just over 50HP.

A typical one has the power valves removed, otherwise stock internals, stock porting, stock piston and head. The key is the pipe and carb.

And, many of those engines are quite old.
 

2strokerfun

Member
May 19, 2006
1,500
1
Old thread, I know. But on the point of bike weight, I don't think they have appreciably changed since the original Honda Elsinore came out in 1973. Yamaha had some late 70s, early 80s porkers probably somewhat due to the shock/swingarm. But even those weren't a great deal heavier than what you see now. The lightest works bikes ever were in the early to mid 70s before the AMA put in a minimum weight rule. Some of the factories had to put lead in parts of the frame to increase the weights when the rule went into effect. As others pointed out, it is the suspension that makes todays bikes vastly superior. But look at the films of the old riders and they were probably going darn near as fast as todays riders. Just didn't have as many crazy ass jumps to contend with.
 
Oct 10, 2000
243
0
Got back into racing this past winter, had sold off my 02 WR 250F along time ago.
Asked the o'le lady if I could get another bike and she "umm ok"
So got an old 93 RM 250. Sent the susp. off & tuned in, Applied triple tree, upgraded some parts/bearings/IMS wide footpegs, put on bark busters and am now racing against mostly 2010/2011 4 strokes in my class and am loving it (finally after I worked out the bugs). Got my first win a few weeks ago in the Sen. B class and now bumping up to A since my condition is back and the bike is right and overalls are within the A class times.

Here is a vid. my daughter made at the AMA Vintage Harescramble in Ohio a few weeks ago of the 93RM at work.
http://www.youtube.com/watch?v=qGJZhR50AVQ

CID__downsized_0306011531a.jpg


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OLD BIKES ROCK!
 

Someone

Member
Mar 12, 2001
865
0
Casper250 said:
There's a guy in my racing district that looks like he came from a time warp from the late 80's. His bike, his gear, his truck are all from the late 80's and he has to be in his late 30's early 40's. This guy flat out flys on the track. He came in 3rd in the 250 expert class and was in a bike length or two of second place. The first and second place guys were riding 450's and he was riding an old CR250.

His bike looked stock. Stock seat cover, stock pipe, rear drum brake, and neon blue grips. So I would say that older bikes will always be as competative as rider who rides it.

Dood, get that on video, or convince him to wear a helmet cam. I would love to watch that.
 

Matt90GT

Member
May 3, 2002
1,517
1
YZ__rider said:
http://www.suzukicycles.org/RM-RMX-series/index.html?RM125_1981-2003.shtml~isoraami

Seems hard to believe, but this website claims 40 hp on a RM 125, although I have to question the legitimacy of the source.

yeah sales brochures never lie! :rotfl:

37-42hp was typical in a cr250 from the production rule until the reed valve motors. Now that is a 250. the 125 was down about 10hp and about 3/4 the torque!

The 02-07 cr250s are dyno kings, but that related to a pro only powerband on the track and you hear the complaint "weak bottom end". But sweet top end that tore up the dyno numbers. I have a 02cr125. has plenty of top end for sure, but NO torque down low. Even the cart motors are great up top, fall off the pipe and less than 1/2 throttle and you will hit the WHaaaaaaaaaaaaaaaaaaaaaaaa bog city!

Point being, what is printed is not always acurate. HP is not the biggest factor. you can have more HP and still have a crappy motor for the masses. Also torque is just as important as HP, thus the 4stroke bikes!
 

The Redrider

Member
Jun 14, 2019
238
32
The numbers for these bikes are wrong. Most 2 strokes from the 80's up made an honest 50 hp at the flywheel. Since the mid to late 90's up they now claim bikes and most vehicles don't make the claimed horse power due to drive train friction. I say B/S, when an engine comes off a dyno, no matter what it is, that is the engine's horse power rating, period. So you can be proud of your scoot when you go to the track and ride it around like a hero because you are harnessing all that power! Ride on Hero!
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