How do the "big minis" compare? KX100, CR expert etc

[motometal]

How do the "big minis" compare? KX100, CR expert, RM85L?

I'm a 5'11" 160 lb adult that likes to play on a mini bike. I've had two KX100s, and have been looking to update/upgrade. Current mount is a 2000 KX100.

I understand that in '01, they updated the cylinder design and increased power, as well as a few other minor changes in '02. Is this significant?

I have been looking for a low hours, clean '02 or newer KX100, went to look at two of them found on the popular auction site, both ended up being ragged out and very bogus.

Now i'm wondering if I should also consider the CR85 expert? It has the same size wheels, and fairly similar physical dimensions. Can anyone give on opinion/impression on the seat/peg relationship and how the CR feels overall compared to the KX? The KX is "barely big enough" for me to ride, but I have an absolute blast every time I ride the thing.

Then there's also the RM85L, which is the big wheel version but is obviously at a displacement disadvantage from the KX.

What about the KTM? Any opinions? Can't find any info on their website.

I may end up just trying to find a holdover/leftover bike at a dealership once I pin down what I want for sure.

 

[FruDaddy]

You can purchase big wheels for yhe YZ from Yamaha. Naturally, this comes at a price. I think the conversion reaches about a grand.

 

[Cr85RaCeR607]

I have an 04' CR85 Expert and rode a KX100 not to long ago. What i noticed is that is had a little more low end, but my CR has a pretty good amount more top end than the KX. The suspension is good on both bikes also. i dont think you can go wrong with either one, Just get the one that is easier on your pocket.

 

[Jasle]

The RM is only the same as the KX in the 65 class. Different bike in the 85's out of the 3 the RM seems to have the best stock suspension. Takes the least amount of $$ to get it right. Or so our suspension guy says.
The CR has no power valve and with my rider there was a very signifigant difference from the RM/KX/CR. He was by far slower on the CR. Next the KX and then the RM he was the fastest on. If you know how to ride in the powerband then the CR is a good bike but the sacrifice on the bottom end might be a concern especially at 160lbs???

 

[motometal]

well, it sounds like the KTM and Yamaha are "out". Evidently KTM had a lot of engine problems and poor sales, and quit making them.

CR85-I know the CR has a lot more of a "hit" since it doesn't have a power valve, but do you really think in a drag race a new CR would equal or beat a new KX100? If so, that's impressive with the smaller displacement.

Jasle-Sounds like the CR runs more like a typical 125 (they have very little low end). I have no problem keeping in the powerband, although in the woods it would be nice to have more bottom end, but that's not a deal-breaker for me.

It looks like in '05, Honda updated the motor and a few other things, so I might want an '05 if I get a CR. It's always hard to tell if these changes are significant. If you look up the specs for the '05 vs the '06, some of the numbers like the wheelbase have changed, yet it doesn't indicate that they changed anything in the description. Maybe they changed the swingarm?

I'm still looking for input on the ergonomics of the two bikes for a 5'11" rider, how they compare. If the leg room is tighter on the CR, I could add a tall seat and bars, but there are limits to this before some point where the feel of the bike gets goofy.

 

[Rcannon]

The 05 cr added a flat side carb. Honda also changed the exhaust manifold. The bikes runs almost the same as the 04. The new carb MAY have given the bike a hint of low end and more midrange. Then again, after spending 3000 on a mini, your looking for anything!

 

[Rich Rohrich]

Motometal - You know this is the bike you really want :)

http://www.servicehonda.com/junior.html

 

[motometal]

Rcannon-regarding cost, yea I found out there are actually many dealers that still have '04 and even '03 KX100s brand new. So far, haven't been able to get them to drop much on price, though. They mention not wanting to sell below cost...it's three model years old! If they don't come down on price, they will just have it for another year. Haven't done a dealer search for the CRs yet. Was hoping to find one to sit on, no luck there yet.

Rich-that Service Honda unit looks awesome! As I read through the specs, my mind was saying "yes, but it's gonna be at least 210 lbs" but 180...that's pretty light for a four stroke with electric start. Looks like the same seat height as the KX and CR, maybe a bit shorter wheelbase. Unfortunately, out of my budget for now.

 

[motometal]

Ok, the latest in the search for a new toy, after reading hours and hours worth of old posts and consulting with a suspension expert, I have come to the conclusion that the RM85L is probably the best bike out of the ones I mentioned, at least for my purposes. I want low end for tight trails and goofing off, which rules out the CR. And suspension wise, the KX is working with '90s technology (although I must admit it worked ok for me once I tweaked it a bit). So, i'm going after an RM this time, and will put on high bars, possibly a high seat, rejet and regear.

I can find '03 leftovers for very cheap, but I may end up with an '05 in the end. There were many updates/upgrades in '04 and '05. Found a few old posts regarding weak frames, and this was upgraded. Hopefully, the upgrades were significant because it looks like I will pay about $700 more for the '05.

If any of you think i'm on the wrong track or overlooking something, speak now...

 

[bikepilot]

I think your on the right track. We got a KX100 for me wife (and for a playbike for me, I'm the same height and weight as you). The bike is an 03, has taller and farther foward bar clamps, flywheel weight, home made power-now thing, 105cc stroker motor, .39kg fork springs, 5.4kg shock spring with R&D rear link and probalby other stuff I've forgoten. It works really well for me, the suspension is fairly plush, but stays up in the stroke as it should and doesn't bottom easily. The motor pulls well and the new style body work (I previously had a 91 KX107 (bored, ported KX80BW)) is a definate improvement. I was really impressed with the non-powervalve motor and the new motor seems slightly better, but not as much so as one might hope. Also, the new cylinder can't be overbored like the old one which limits you to stroking if you want more from it.

We went with the KX because I liked my old KX and we found an awsome deal on this one. If we were purchasing new I'd certainly look seriously at the RM85L. I have not ridden one, but at the last harescramble race I was at (a couple of months ago) there were more of them then KX's in the supermini class and were praised by their owners for great suspension and smooth, strong power.

 

[Vic]

I have an ' 03 RM 85L that I will let go for $1600. It's completely stock, except for jetting and a turn down modification that I made to the silencer. I bought it from a girl who used it twice,but was afraid of it. I used it mostly for trail riding with the kids. I think I've only had it on a track once. Even the tires are still stock and in good condition. The only time it's been on the ground, that I know of, is when I dropped it in a slow turn tip-over. The bars are stock and straight. The only ugliness is the shredded tank graphics. If you want it, you will be responsible for picking it up or having it shipped.

vic @ dirtrider.net

 

[motometal]

thanks for the offer Vic, but I ended up buying an '05 (new) today.

Haven't ridden it yet, but my first impressions:

Motor sounds great

surprised to see an old school round slide carb on it?

suspension clickers don't have clicks, you count turns

several items are engineered thinner/lighter/simpler than most other bikes i've seen. whether this is "good engineering" or "corner cutting" remains to be seen.

but, the brakes and rear shock are larger/more heavy duty than the KX

cables are borderline too short for the "mini-high" bars I put on. Didn't have an issue with this on the KX.

Seat height is about 1.5 inches taller than the KX. This could vary a bit depending on suspension adjustments.

seat-to-peg distance is about 1/2 inch greater than the KX.

handlebar to rear edge of seat is a bit shorter than the KX.

Can't wait to ride it.

 

[tnrider]

keep us posted as to your mods and satisfaction as i am looking at something like this to play on too.

 

[motometal]

Ok, here are my impressions so far, after the maiden voyage of the '05 RM85L tonight. Right off the bat, I could tell that the ergos are more roomy in general than the KX. Sitting to standing transition is better, I'm running tall bars, might look for a upper triple clamp that moves the bars forward, also I wouldn't mind trying a tall seat, although the stocker is not far off for me at 5'11". It is flat and firm, very comfy.

The shock spring is too soft for my 165 lbs, but really not as far off as you would think. I'm at 92mm sag with about 15 mm of static.

The fork springs are further off for my weight, I can push them almost 3/4 of the way down just pushing on the bars with the front brake on.

Overall though, the suspension has some real potential. Both front and rear feel surpisingly stiff/firm, without being too harsh (although it will probably soften up some with break in). This is with neither the front or rear compression adjusters anywhere close to max. I immediately felt comfortable enough to do a fairly tall 50 foot double, the forks might have bottomed but not hard-both front and rear appear to have excellent bottoming resistance.

After the 45 min of breaking it in, I was ready to try out the engine-it's been awhile since I rode the KX, and that's all I have to compare it to. My KX is a 2000 with the updated larger carb and other minor mods. The RM definitely feels softer way down low, typical of a little motor with a big carb. THe round slide carb may not be helping matters any, jetting is not too bad but generally flat or oval slide carbs give better low to mid response, I may try the one off the KX.

Anyway, once you get into the midrange it's wakes up, and there's plenty of smooth power just before the powerband kicks in. It revs out "ok", not to the moon but good power and this is still with the stock main jet. Very easy to bring the front end up all the way through 4th gear, and by that time you are moving right along. As long as I was on the gas, I didnt have any problem with bogging, it pulled quite well and the gearing isn't any too low or tight. Porting/exhaust/jetting to just let it rev out a bit more on top would really complete the package, but it's pretty fun as is.

I goofed up the rear fender removing the safety sticker.
Almost like it was painted on, and the fender is not made of very durable plastic.

Nearly looped it wheelying over a thick vine that was suspended about 20'' off the gound. Clutched it up a bit too much in 1st gear, it went vertical RIGHT NOW and I was going to loop it, stabbed the rear brake just as I got over the vine, couldn't grab the clutch soon enough and I killed the motor. This tried to toss me over the bars, but then the engine bump-started and all was well. Would have made a good video!

the trans shifts so easilly, you can't hardly feel it. The lever seems to have more leverage than it needs, but the position of the lever is fine.

The bike starts like a dream, and weighs in at 158 lbs full of fuel. My KX weighed between 170 and 180, but this was with the motard wheels on it (that I need to sell).

mods: already did 756 front tire, tall bars
next will be:spring(s),
upper triple clamp if I can find one,
tweak jetting and/or different carb,
possibly gear it down a bit
nitrous

anybody know of a good source for the upper triple clamp?

 

[Vic]

I think Applied and Tag have one too, but this looks like the best deal.

http://www.rockymountainatv.com/pro...Control&webCatId=12&webTypeId=70&navType=type

FWIW- I run a BR9ES plug. I dropped the needle one notch, went down two on the pilot and one on the main (can't remember the numbers off the top of my head).

 

[motometal]

Vic, thanks for the info. What is your elevation?

I went one leaner on the main (125) and i'm not sure if it needed it, may rev out a bit better but not drastically. The spark plug looks a bit on the light side, but then i'm running the "9" as well. I may run a "10" next time and see if it still looks lean. The gurus would yell at me for jetting by looking at the insulator of the plug.

I'll be hooking up with a set of clamps, the Longhorn ones look great but i'm unclear on the rise measurements, I don't really want them any higher because the cables won't work.

After riding it some more, i've come to the conclusion that the motor works way better on the track than it does in the woods. Don't get me wrong, i'm having a blast on it in the woods but could actually go faster on my 250, even in the tight stuff. The dry conditions here make it tough to keep on the pipe. By the time I do a few mods and get more time on the bike, it will be fine.

Again, the suspension on this bike works really well, considering I don't even have the right springs for it yet.

The toughest part is deciding which mods to do, might try a flywheel weight but this is going to get expensive...bike+springs+triple clamp+flywheel weight...

 

[Vic]

I'm at sea level, roughly.

You might try turning the powervalve spring pre-load adjuster in a quarter turn. That may give you the power delivery that you want without having to resort to a flywheel weight.

 

[motometal]

Ok, I'll take a look at adjusting the powervalve. Another "excuse" to go for a test-n-tune ride would be great.

I emailed one of the companies marketing the adjustable triple clamp (one is Longhorn on RMC that you suggested, there's also a copycat on "popular auction site") and found out that the unit weighs 3.5-4 lbs. I removed the stocker and weighed it, as I suspected it weighs 1.5 lbs. It is cast and hollowed out significantly.

So I like the adjustability of the aftermarket units, but not real enthused about adding 2 lbs way up high. The fork clamp area (which is way taller and has three bolts instead of one) is way overkill! If I had a mill, I could probably shave the unit down quite a bit.

 

[ragingbull]

Hey motometal, if you still have the motard wheels for the KX hit me with an email to [email protected] as for some reason I can not hit you with a PM...

 

[Martin Cole]

Hi, we found most of 85s to be pretty even on performance but for a tall rider the Suzuki RM85L is probably the best bet if run stock. It has the highest seat height and will probably be the most comfortabe if you have long legs. If you want the extra power of a 100cc engine you can certainly have the RM. CR and KX bored out. The KX has another advantage in that you can get different length suspension linkages to raise or lower the ride height.
MC.