fastducs

I shelled out a painful amount of money for a Vmar brake pedal, and that solved the problem. The pedal is billet, and it is shorter than stock, so it hides out of harm's way.

Here is how to shorten the GG-50 forks: take them apart completely, including the damper rod. Remove the plastic spring preload spacer. Fabricate an aluminum spacer of same length, and install it onto the damper rod below the topout spring. There are a few tricky details, such as the bleed hole, so if anyone wants to see pics PM me your email addr and I'll send them. This method maintains proper spring preload while making the forks shorter by 1.5" which makes for much better geometry on this bike IMHO. You've done an amazing amount of work. I'm very glad you did it instead of me. I was tempted to try, but then I came across a 2006 GG boy-50 and we never looked back. My son rode the wheels off of his Oset-16 and even with 36-Volt motor he always wanted more power. It was obvious to me that power density of batteries is still far behind gasoline. I wish that wasn't so, as I was/am a huge fan of the Oset, and really miss those days when he could ride in the park and nobody would complain. Now we have to stick to the woods, or to our back yard. As for your weight concern: I can tell you that a 60-lbs kid on the GG-50 works just fine. Kids are amazingly adaptable. Plus it has the "training" clutch, which he is slowly learning to use - all in the name of popping bigger wheelies ;-)

The owners manual has a pretty good description of procedure. As far as forks go, this one is not very complicated. So if you don't have a manual, then search the web for how to take apart a conventional cartridge fork. The only special tool is a cartridge holder, which you can make yourself, or you can do without it if you have an air impact wrench to remove the bottom fork bolt.

What jets do you have in it now? What about air screw? And which exact carburetor model? My son's 2006 starts reliably hot or cold. When hot, it likes the throttle wide open before I start to kick. If for some reason it doesn't fire up after 2 or 3 kicks, then I close the throttle and push (as opposed to kick) the kick starter through several cycles. You'll know it's ready when you feel some resistance. Then open the throttle and give it a kick, which usually gets it going.

Carbon buildup on the piston and/or on the head will raise compression ratio, not lower it. Plus, carbon has a tendency to glow. Those two factors can be contributing to your detonation problem. But another issue is the temperature, which affects jetting requirements. If you are running with the same jetting you had in the summer, then it might be too lean for cold temperatures. Also, gasoline blends which you buy at the pump are seasonal, i.e. the oil companies blend them differently based on the season. The only way to have consistent fuel is to buy expensive race fuel in canisters.

There is really no single "correct" mixture screw setting. So for what it's worth, my air screw is 2 1/4 turns out from closed. The rest of my carb is set up as follows: main jet: 70 pilot jet: 36 starter jet: 50 slide: #40 needle: type A2 with clip in 2-nd from top groove My starting procedure when bike is cold: 1) choke ON, throttle completely closed 2) lazily push kickstarter several times until I start to feel occasional resistance 3) give it 1 or 2 swift kicks and it should start. But if it doesn't, then go back to step 2 4) turn off choke pretty much right after it fires up My starting procedure when bike is hot: 1) choke off, throttle WIDE OPEN 2) several swift kicks gets the motor running

1) Go here and find your part number: http://www.apexmotosports.com/montesa%20parts%20book/e-1.htm 2) Take that part number, then go to http://www.ronayers.com/ and plug it into "Where Used" dialog box to see where this part # is used. For example, your Monty's con rod small end bearing 91015-KZ3-003 is used on 1990-2007 Honda CR250R. But crankshaft 13300-NN3-000 doesn't come up on ronayers.com, which means it is unique to Montesa. As a rule, any part number with -NN1- or -NN2- or -NN3- in the middle is unique to Montesa.

Just went through those symptoms with a friend's bike. Almost brand new bike, idles but won't rev worth a damn. Took the carb apart, checked compression, spark, all was within spec. So I'm thinking vapor lock in fuel tank, or some other restriction to fuel flow. I pulled fuel hose off the carb and turned on petcock to measure fuel flow into a calibrated container. Lo and behold, about 200cc of water come out. I am surprised the bike ran at all. To this day my friend doesn't know how the water got into the fuel tank.

I've tried Mobil-1 synthetic ATF, and I've tried BelRay GearSaver 80W tranny oil. BelRay works better IMO. I have no issues with stuck plates or clutch drag. You can get it at most bike shops and on-line. BTW, I don't know if it matters any, but I noticed that when I drain the ATF it smells really nasty, whereas BelRay does not. On my list of things to try is AC Delco/GM transfer case fluid. It is blue (pretty color!) and I use it in my kid's bikes with auto clutches, but haven't tried it in my Mont yet. A friend with GG uses it and likes it. It is available from any GM dealer, but unfortunately auto parts stores don't carry it.

Sam, that's a great find. I'll be doing my forks this winter, so this definitely helps. BTW, where did you find this cross-reference info? I'd like to figure out if seals match too.

full protection if you want them to continue riding after their first serious get-off. Adult elbow pads make good knee pads for kids. Elbow pads are a must. Check out hockey elbow pads for small sizes. Fox comp 5 boots come in very small sizes. Chest protectors come small, but you will have to shop around. Hockey gear comes in very small sizes, which was my son's first chest protector. Full-face MX helmets come very small. So do ski helmets, which was my son's first trials helmet.

Yes the Showa shock can be rebuilt by a suspension specialist. I had mine rebuilt by Peter Kates at http://www.computrackboston.com/ He even machined a replacement rebound adjuster as mine was seized and broken.

My son had a 36-volt version from day 1, so I can't tell you how much slower the 24-volt version is. But I will tell you that a 36-V with a light rider on board (50 lbs) on max power setting is a little rocket ship.

I don't have a Rookie 80, so I can't comment on that particular bike, but I've had to adjust suspension for several other bikes for my son. Have you already ruled out excessive stiction (e.g. bad seals or bushings) as well as fork misalignment? If the forks are twisted in the triple clamps, or if they are not parallel between the axle and the triples, then they will bind for sure. The triple clamps themselves can be tweaked, or twisted relative to each other. The front fender also acts as a fork brace, so if it's not installed with proper amount of shimming, it will pull (or push) the forks out of parallel. Same goes for improperly tightened axle. There is a bunch of fork alignment info on the web. Here is one example: http://w6rec.com/duane/bmw/forktool/index.htm Too much fork oil will make the last part of fork travel overly stiff. But from your post it sounds like your son is having trouble with the first part of travel, which is mostly a matter of spring rate. If you cut down the spacer, you will be reducing preload, which may help somewhat but it may not be enough compensation for a too-stiff spring rate. Basically there is no substitute for correct spring rate, and preload spacer is only there to do minor adjustments (primarily to set sag correctly). The first thing you'll need to do is to measure the spring rate. If you have a suspension shop, then they can easily measure it for you. Or you can measure it yourself using a ruler and a digital weight scale. Spring rate is measured in kg/mm so place the spring on the scale, compress it by 100mm and then divide scale reading by 100. There is also a formula floating around, but I don't know how accurate it is, since it assumes all steel springs have the same spring constant. K= (W^4 x G)/ (8 x N x D^3) Where: K = Spring rate in pounds per inch W = Diameter of the spring wire in inches G = 12,000,000 for steel springs (a constant) N = Number of active coils (number of coils that are free to move + 1/2 coil) D = Diameter of the coils in inches (I believe D is measured to the center of the spring wire. So, take the overall diameter of the coil spring and subtract the diameter of the wire (W) to get D.)

I just looked at the pics I took when I rebuilt my carb. I can confirm that there are no other bolts holding it. Give it a love tap with a rubber mallet and see if comes off. The gasket is actually a rubber o-ring that sits in a recess that's machined into the float bowl mating surface. The carb body mating surface is totally flat. So if worst comes to worst, you can use a stiff razor blade as a wedge, as long as you don't insert it too far.