Picked up a very nice, low hour RM 65, 2003.

It's running stock jetting, one tooth down on the front. Other than that, it's stock, except for tires and handguards. The PO said the gearing change really made it easier to ride in the woods. Opinions?

stock gearing?

dropped the needle a to #2 position and the bike responded very well. It had a bog off idle before. Now, it may be too snappy.

What's a good size FWW? My son has been riding a PW 80 and this is quite a change. He rides woods and rides very smooth, so I want to smooth out the power as much as possible. I will likely be doing the washer mod as well, at least to start.

I would also like to hear where you get parts from, reasonbly priced?

Any other advice would be appreciated.

He's 8 BTW.

I will get some pics up soon.

I'm interested in fly wheel weights also. I just bought a KX65 for my 8 year old who is currently riding a stock KLX110. I take it the FFW just bolts onto the stock flywheel?

if it works like the big bikes, then yes. I believe Steahly makes them, but not sure of the best place to buy them.

My son just got rid of his kx65 (he just turned 10) but unfortunately we never used a flywheel weight - he mostly rode track but every once in a while we did some gnarly trails - he never had issues on the trails with the bike stock, it's an easy bike to ride - very forgiving most times.

I hope I can help you out on this one. Like you, my daughter is coming off a PW80. She's 9 and has been too tall for the PW80 since the day she got it. We got the KX60 last weekend.
I spent a lot of time trying to find a manufacturer other than Steahly for a KX60 FWW.
I didn't find one.
Yours uses the same FWW, but needs extra cover gaskets, you'll need Steahly part number 605. http://www.steahlyof...5&weightsPage=2
Costs about $115 + shipping from just about everyone. So you might as well get it from the source.
I went with the 12oz weight, but perhaps that's not the best one for you though:

Ask me next week how it attaches to the flywheel. It looks like it's held on by a central nut/bolt to the crank.

Thanks Smac and Matt. I am doing some of the things we talked about in the other thread, washer, etc.

That's a helpful chart. Looks like I will be going with the 12 oz as it describes him to a T, or how I want him to ride.

I imagine a 12 oz FWW and washer in the exhaust will allow him to concentrate on clutchwork and getting used to the new bike.

I wonder if there are any tamer needles, or if it even matters on such a pipey engine.

On our 04 RM65 for woods racing we did the Eric Gorr suggestion:
Have the cylinder base turned down 1mm to lower the ports
and recess the head 1mm with a 10 deg. squish angle.
More lowend power and it seems more linear power too.
Only cost me $45.00 at a local engine machinist.
A FMF Fatty pipe works better than the stock pipe for woods use.
The Moose ultimate clutch lever and perch works great for small kids
with little hands.

TS,

Thanks for the info. I'm planning to pick up a spare cylinder and have it sent to Eric for a more woods friendly machine. I figure those last three words are all he needs to know to make it possible. $45 at the machine shop over $125 to send it out sure is tempting though.

Depending on what type of rider she turns into with this, before she's tall enough for her next bike (this kid is a weed, grows so fast and yet I want her to stay "little" at the same time.), I may consider adapting the same theory in the Kawasaki RS03-01 bulletin to the KX60 on the original cylinder. I'm going to take a wild guess that this can be done verbatim on the RM65, but you should do a little more research to confirm it before jumping right in if this is what you want.

Good suggestions, but I am not going to invest a lot of money in this bike. I won't be tearing into it if I don't have to.

I guess it really depends on how he progresses. But, for now, I can't see spending a lot when my bike needs stuff too. Once he gets used to it, then I will look at these other options.

I can't even make myself buy a new pipe for my bike, can't see spending almost a 1/4 of what I paid for the bike, on a pipe. hehe :smirk:

Oh, I know exactly what you're talking about.
That's part of the reason she's got a 60 and not a 65.
I try to do what I need to do as cheap as possible. But the $125 that I might spend would make this a much, much better woods machine than it is stock.
That Eric Gorr guy wrote the book on tuning smokers and all.

if you change the gearing on the bike, you can turn it into a decent woods machine without much else - gearing, the fender washer to start, and teaching your kid how to use a clutch properly is probably all you need to do. Once they know how to use a clutch PROPERLY - the flywheel weight will likely be redundant too (I think those are extremely overpriced little pieces of metal), I never spent a cent on additional stuff for my kid's 65 and he rode woods, rock fields, knarly hills and about everything else just fine - actually - better and faster than most adults in our club, but he got the hang of the clutch (and I swear that's 99% of it) quite quickly and it all became easy to him right away.
For how long kids have these small bikes, it just doesn't make sense to throw money at it that you'll never recover. Just use this time to teach them how to ride properly and you'll spend less money in the long run modifying bikes to make certain tasks easier.
Sure - there's bikes designed and set up for specific tasks - look at trials bikes - you'd think you could never do that on a full blown MX bike....think again - you ever see the crazy Romanians do any and all trials stuff on MXers? Absolutely amazing, and definitely NOT impossible.

I agree, $115, or in my case $104, is really expensive for a metal Frisbee. I looked at the part and what I estimate it would cost to have a machine shop make one (and seriously considered some DIY possibilities) and decided that buying the manufactured piece is the wisest move. I'm taking a wild guess that it's at least hardened to reduce the likelihood that it'll shatter. I also have to remove the flywheel cover just once.
My daughter enjoys riding. But she's also easily scared off the bike and easily frustrated, so that's why I'm doing the FWW mod.
Her brother? That kid, provided that he wasn't seriously injured, would probably get dumped off the bike a dozen times and get right back on. Thinking back, it only took him a half dozen tries to get the clutch down when we moved him from a XR50 to a DR-Z125. We unloaded it (purchased used), all he wanted me to do was adjust the clutch and he wanted to ride it. Well, I knew from my pre-purchase evaluation that it needed a good carb cleaning, oil changed, suspension made softer, forks dropped in the trees. He didn't care if he needed to mount/dismount by pulling up to a milk crate and leave the choke on, all he wanted was to ride. It could have been totally mangled, as long as the engine was running, he would have attempted to ride it. In fact, he did. I got the clutch adjusted and started the oil change (engine was hot from the clutch adjustment), he kept bugging to ride, ride, ride. Finally, I let him. A while later, I got to finish and he tries it out again. "Boy! That's so much better!". He's still learning that typically the old man isn't a crotchety old stickler for details, usually I have a reason for everything I do.
My daughter is much more delicate. Ironically, her brother has repeatedly stalled the KX, since he's used to the DR-Z which you can practially dump the clutch at idle and it'll still keep running.
I anticipate she'll be on the KX for this coming year and most if not all of the year after. Because of all this, I'm willing to invest more to make the bike fit her and her riding style, which is still developing. I think once she's got the hang of it, she'll be a pipey type of rider, time will tell. Until then, I'd like to minimize frustration on her part and mine. $100 is worth it.
Also, this FWW fits a KX80/85 and KX/RM100 too (not RM80). So it may come into play in the future.

I'm curious, what would you recommend for changing the gearing? Drop the front one, two teeth? Considering how inexepensive sprockets are, I'm willing to try several until we get it right.

I agree with Matt on proper clutch usage. My son picked it up quickly and can ride pretty much any trail as well as on a MX track. The pipey 65's make you pay more attention to what the bike is doing, and I think a better rider.
I do suggest full gear and a neck brace, won't be long before he starts going vertical!

mine is down a tooth up front. 1st seems useless and 3rd chugs along well, as does 4th.

I AM doing the FWW. The little bike has quite a powerband on the pipe and actually kind of skeered me. It pulls the front wheel off the ground with me on it. :eek: Last thing I want is my son to get too much throttle and get shot off the trail. The bike needs taming for the type of riding we do. If I could easily make it PW80 smooth I would. I think the washer in the exhaust and a FWW will be a good starting point.

And as said, I can resell the FWW later and get half or better back.

I understand the flywheel weight will also make the bike harder to stall?
I wonder if it is possible to buy the heaviest fww and have it turned down (lightened) as the child's skills advance.

gmoss said:

One thing to remember, you, an adult are outside the intended rider's weight and height. Because of the extra inertia your body places on the bike, changes the center of gravity too, the bike is more likely to want to rotate under hard acceleration, which we know as a wheelie. A kid (80-120 lbs), it's going to tranfer this rotation to forward motion instead most of the time.
I said to the guy we traded the KX60 our PW80 for, that if Yamaha made a PW100, or even a more aggressive PW80 in a larger frame, I'd buy it. She loved that little bike. I did too, all you had to do to it was add gas and oil.
I'll be going over the pre-ride checklist with my daughter after she gets some seat time in with the KX.
Ours has the 3/8" ID fender washer in now.

Wandell said:

Makes sense, but I'd talk to a machinist first. It depends on the material primarily, I'd also expect it to be balanced, machining might affect that in a negative way.
Yes, additional flywheel mass should make it harder to stall the bike. Think of the "hit and miss" or "rough riders" engines from way back in the 1900s. They had a massive flywheel on them because the motors were not so smooth and also to help start the things cause they were so finicky, a couple of extra revolutions made the difference between starting one and swearing at one.

I just purchased a 05 RM65 and put the 12oz FFW on the bike. I was riding it around the yard and the hit was insane like a light switch (off/on). This bike is running the pro-circuit pipe so I’m sure that’s not helping the bottom end much. We are going to be 100% yard and woods so taking the hit out wasn’t that big a deal. With the roots, mud, rocks and hills in the Seattle area a little more rotating mass will be good. I figure if he gets better and we take off the FWW or put on a smaller one and I will sell the used one to someone for a good price. One size fits many so demand will be there, I don’t think you can really go wrong.

I also put a washer in the exhaust to see how that changes things. Wow, no hit at all… Good for learning the clutch for sure. Even if my guy pins the thing it should be no faster than his CRF50 he’s riding today. He’s getting almost all you can get out of the CRF right now.

I think the biggest problem is when things go wrong they go wrong fast on many different levels especially on a 65. If you overload the brain with too much input you can freeze up being a new rider. I’ve seen it on the track where someone bites a little more than they can chew and they kind of overload. I’ve just put in a couple of safety nets to help that problem. When the brain catches up with the bike some of the extra safety nets can come off.

Ride on!

I agree Tomsti.

Where are you guys finding the best deals on parts?

MXSouth has some decent prices.

FWW, air filter, gripper seat cover, etc.

gmoss said:

I've just purchased the FFW and the gripper seat cover from my local dealer. The FFW doesn't seem to fluctuate in price too much. The seat cover was also priced right. The washer was found in the garage.. I actually I couldn't believe I found something that fit in my garage. :)

Tomsti said:

I'm thinking along the same lines as you. My 8 year old is riding a KLX110 and I just purchased him a 08 KX65 for Christmas. I'm currently letting him ride my Pitster Pro X4 around the yard to learn clutch usage. I know the KX65 is gonna be a big jump being much faster, a two stroke, a clutch, etc. I'm thinking of adding a FWW and doing the washer mod until he masters the clutch and then adding a little of the power back.
Tomsti, have you removed the FWW yet?