Will the rm125 be good for me

[bully_23]

Hi everyone I'm in the market for 125 class motocrosser and I was wondering how the rm125 would be I can pick up a killer deal on an 05 model and save like $4000 aud on a brand new 06. Im a bit of a novice but i know how to ride. The only other motocross bike I have ridden is a 01 yz250f It seemed to have the right amount of power for me and wasnt 2 scary. now how would it stack up against the 4 strokes performance wise I know it will be cheaper and easier to maintain which is good but I am worried i wont be competitive in mx when i start......would the exhaust system it comes with help. Thanks alot sorry for the long post my details and the bike add are below
1) your physical size 5"6 160 lbs
2) How physical / aggressive are you ? agressive but cautios sometimes
3) what do you plan to ride- MX/SX tracks, woods, fields with friends or ????? MX and just around fields and small trails
4) Do you have any riding experience? yes on a honda 50 and recently a chinese 150cc 4strk (piece of crap lol)
5) Do you think you will race ? yerp
6) Are you mechanically inclined and will you be doing your own bike work? Im not very inclined but i will learn my dad knows a bit but not heaps. Dirtbikes isnt something he is into

Ad Details:
MAKE/MODEL: Suzuki RM125
YEAR: 2005
PRICE: $5,500.00
ENGINE: 125CC
CONDITION: Very Good Condition
Comments...X-RACE FULL EXPANSION CHAMBER EXHAUST SYSTEM WELL MAINTAINED FAST NO FUSS FINANCE AND INSURANCE AVAIL.

 

[robwbright]

Bully:

This is going to be long, but I think it will be educational for you . . . LOL

First, as Eric Gorr says, "Speed is 95% rider and 5% bike. Better make that 5% count."

The 250F's have about the same peak horsepower as a 125 2 stroke - i.e. stock 125s and 250f's have about 31-33 HP stock. However, the 250f's have a lot more torque on the bottom end and midrange. Most people find them much easier to ride because you don't have to shift as much and the power delivery is more forgiving.

However, the 125's are lighter and generally handle better than the 250f's - i.e quicker cornering. Further, most people think that the 2 strokes are more fun to ride because of the extreme "hit" of the powerband in the mid/upper midrange.

I prefer the 2 stroke because of the weight, ease and amount of maintenance and the fun factor.

The 250f definitely has an advantage over the 125 on the track - I find that the advantage is evident mainly on the start and while exiting corners. The 250f tends to pull quicker without wheelspin. On the 125 you have to feather the clutch and learn to be precise with the throttle.

Nevertheless, in my first season of racing last year on a 2002 RM125, I had four 2nd place finishes in my class(es) in about 12 total races. I was able to beat numerous 250f's in the course of those races.

Since speed is 95% rider, if you're on a 125, you will beat almost all of the guys who arenot as good as you are. If you're racing head to head with a guy of equal skill, you will have a lot of difficulty beating him on the 125 if he's on a 250f.

That said, having done it already, this is what I would do if I were you and I want to "make that 5% count" on a 2 stroke 125. (Note: again, at the beginner and novice level, the 125 will be fine and you can beat almost all 250f's whose riders are not as good as you, but the following is the ideal setup for a 2 stroke, IMHO).

I would buy one of the 125's and send the motor to Eric Gorr for a 144cc overbore kit. Eric is closing up shop in April for several months, so there is still time to get it to him.

Because of the inherent advantage of the 250f, the AMA is allowing amateurs to overbore their 2 stroke 125s to 144cc. Eric did my kit for $450 and shipped the motor back to me free since I pre-paid. I'm not sure what he's charging now - prices went up in 2006. His website says $475.

This includes boring the cylinder 4mm, having the cylinder re-plated, porting the cylinder to your preferred riding style, modifying the head to the compression you want (pump gas or race gas - race gas provides about 1 HP improvement). The kit also includes the modifications to the low end case, the oversize piston and ring, and re-assembly.

When I got my motor back from him, I bolted it in and it started on the 6th or 7th kick. It now starts 1st or 2nd kick.

As to how the 144 runs, it's incredible. A 144 with race gas will run 37-39 HP - read my following post:

http://www.dirtrider.net/forums3/showthread.php?t=126800

. . .and all the posts in this one regarding reliability of the 144:

http://www.dirtrider.net/forums3/showthread.php?t=124121

. . .and here are some others:

http://www.dirtrider.net/forums3/showthread.php?t=127695

http://www.dirtrider.net/forums3/showthread.php?t=127984

 

[robwbright]

On this topic here are the pics I have found which illustrate the difference.

Here's a 125 piston in a 144 bore:

http://community.webshots.com/mypho...5&photoID=1534778526083773316&security=WREkBY

Here's a stock 03 CR125 vs. an 01 Eric Gorr CR133

http://community.webshots.com/mypho...5&photoID=2326284960083773316&security=aFrhat

And here's an 01 Eric Gorr CR 133 vs. a stock 04 RM 125:

http://community.webshots.com/mypho...5&photoID=2209352990083773316&security=JHdsKb

The 133 is a 2mm overbore and apparently provides a quicker reving engine than a 144, with about the same peak. A 144 will have more low/mid than a 133. Unfortunately, I've been unable to find a 144 dyno. . .

 

[bully_23]

Thanks alot for the info Rob it was very helpful I would also like to know specifically about the 2005 rm125 any one with this bike that could tell me how it handles the motor etc thanks

 

[2-Strokes 4-ever]

In my opinion, the RM is the best handling/fitting bike. Once you get into an intermediate or expert class, you'll need something with more power........but that may be a couple years away for you, and you'll want a new bike by then anyway. Easy maintainance, cheap maintainance, lots of aftermarket goodies, a proven ride......and a TON of fun!

 

[robwbright]

Thanks alot for the info Rob it was very helpful I would also like to know specifically about the 2005 rm125 any one with this bike that could tell me how it handles the motor etc thanks

The RM'S were last totally redesigned in 2001. Thus, the 2001-2005 RM's are essentially the same design bikes with minor changes in engine and suspension. Many parts are interchangable. Thus, my '02 is going to be very similar to an '05.

Plus, each brand tends to have a particular reputation/character concerning suspension and handling and the companies tend to stay within those characterstics. . .

Zooks are known for GREAT cornering and plush suspension.

 

[bully_23]

thanks does anyone else have experience with this bike that could give me some info Thanks again

BuLly

 

[Chili]

My son had an 03 and currently has on 05 RM125, the cylinder underwent some major changes in 04. My son feels his 05 is heads and tails better than his 03 was. The motor is strong and likes to rev out on top, we had the bike ported to help a bit off the bottom. Suspension wise it's excellent and at your weight will be pretty good right off the showroom floor, we went with softer springs, different valving and an air tank system for my son but he was 20 lbs lighter at the time. For that kind of savings and the fact there was almost no changes from 05 to 06, unless your one of those guys that needs to have the newest bike I'd say it's an easy decision.

 

[HajiWasAPunk]

There's 2 guys with RM125s in the beginner class I race in. Not sure about the years but I believe one is a 2005.

Neither of them have a prayer beating me to the first corner, even when I don't take off well. But as Rowbright said, the race is mostly rider and I have lost to both of these guys sometimes from mistakes I made after the first turn.

 

[Chili]

Neither of them have a prayer beating me to the first corner, even when I don't take off well.

Then they need to learn how to start better. I know the 4 stroke is stronger off the starts but if you can botch the start and still beat them to the first turn it's got nothing to do with their bikes.

 

[bully_23]

well I have also seen a 2004 Ktm 125sx in very good condition would this be a better bike than the 05 rm and I have also seen A 2005 yz125 but its $500 more than the rm what would be best do you think?

 

[HajiWasAPunk]

Then they need to learn how to start better. I know the 4 stroke is stronger off the starts but if you can botch the start and still beat them to the first turn it's got nothing to do with their bikes.

Chili, that's a good point. Often times they run the beginner class with the C class. When I get what I would call a good start, I can beat most of the C riders on 2-strokes to the first turn (they get by me before the first lap is up though, which adds to the point that it's still all about the rider). But if I miss time a single shift or body position is less than my best then I don't beat any of the C class 2Ts to the corner.
I would add that a lot in the beginner class has to do with how agressive you are. I think the nerves of 15-20 bikes coming into a turn forces most beginners to back down.

 

[MXP1MP]

If your best deal is going to come from getting the RM snatch it up! Dail in the jetting for your area and go kick some 250F A** on it. Especially in the amatuer scene go's double for beginer classes where it doesn't matter if you was on a new 125 or 250F I recommend the 125 more cause it will make you a more aggressive rider so any bike after that will be much easier to ride. Plus give it a few more years on the 250F's anyways I mean they are changing every year, honda went so far as to offer a gimmick! (daul exhausts!) Get the 125 now while it's cheaper and then after a year I say 144 and keep another year then get a 250F. I'm done with 250F's untill the 2nd generaton motors start coming out that and who knows they might be FI in a few more years. Then by that time you should have the skills to apperciate the 250F more.

 

[BENYZ]

125 awesome!

:nod:check this out!

http://dirtrider.com/tests/motocross/141_0412_125_shoot/

for best 125 ever! :nod:
i like yz!

 

[CamDayKX125(4)]

if you plan on whiping the bike around a lot and being really aggresive on it.(i know, you said you wanted to race), then the rm probably wont be the best 125 for that. the most popular 125s for racing guys(based on what ive seen), is the yz and kx 125. the kx would be better at trails than a yz because of the low end power of a kx. a yz is made for aggresive riding and is either on of off on power. i ride a kx fine on tracks, but dont race yet. (mine is a 00' model though) if you were, say, 5'8'', then the yz would be a better choice because (as ive read) they are made for taller and more of a expert -type rider. a kx would suit riders below that fine.(even though my dad is 6' and can ride my bike on tracks). these bikes arent that much different, but i like the kx better.

 

[robwbright]

if you plan on whiping the bike around a lot and being really aggresive on it.(i know, you said you wanted to race), then the rm probably wont be the best 125 for that.

What's your complaint with whipping the RM around? Mine handles about like my CR80 did back in the day, which is to say, it handles very well.

 

[CamDayKX125(4)]

What's your complaint with whipping the RM around?

i meant it not being best at racing. in my opinion, a kx or yz would be better for that.

 

[Chili]

i meant it not being best at racing. in my opinion, a kx or yz would be better for that.

Based on what, you owning a 6 year old KX?

 

[2-Strokes 4-ever]

The RM's are well known for being light feeling, corner carving, very flickable machines. The CR's, YZ's, and KX's are good bikes too, but the RM is "the whipping" 125.......if there ever was one!

 

[robwbright]

The RM's are well known for being light feeling, corner carving, very flickable machines. The CR's, YZ's, and KX's are good bikes too, but the RM is "the whipping" 125.......if there ever was one!

Exactly!

 

[MXP1MP]

I haven't ridden an rm 125 since '02 and the bike was a near new pristine '01 model the owner was a vet rider who knew little about new bikes so I got to spend half a day on it dailing in the jetting after ridding and racing my '02 yz 125 all year at a familar track. Compared to the my steel framed YZ that I had setup the RM was just as fast definetly alittle more comfortable due to the softer RM seat at the time yz's have some hard seats. The RM did feel alittle better in terms of being quick feeling but not like I couldn't have done it on the yz either! so it was alittle more willing to turn faster and it felt alittle more whippable but it wasn't as stable on though. I would have been happy with it but honestly my '04 kx I could out whip the RM on it. Definetly not on the older style KX's not a chance the new KX's are not really even the same in fit n feel handling etc. I would pick an '00 n up CR over that style KX any day. the KTM are kewl and I like my friends '05 but all I really want from the bike is the hydraulic clutch. It's hard to find a 125 that doesn't handle good.