How To Replace A Dirt Bike Clutch – CR125 2-stroke

If you want to ride or race dirt bikes for the rest of you life, there’s some things that you need to learn how to do and fix on them if you want to save time and money. Replacing the clutch should be one of them, and it’s bound to happen if you’re racing or putting a lot of hours on your bike throughout the riding season. Don’t worry, it’s actually a pretty easy job.

If you’re scared to work your motocross bike, I strongly recommend getting an OEM service manual for your bike if you don’t have one already. The factory manual will have pretty much everything you need to know for maintaining or repairing your dirt bike. There’s dozens of diagrams, specs, maintenance intervals, tips on adjusting suspension, and much more.

First thing is to start out with a clean bike and work area. If the bike is not clean, you run a much higher risk of getting dirt or foreign objects inside the clutch/engine, so at least wash that part of your dirt bike. Having a cluttered and filthy shop area is annoying, and can be dangerous if it’s hard to walk. Make enough room to comfortably work on the bike with clean parts and tools.

CR125 Clutch Cover Bolts
CR125 Clutch Cover Bolts

Once you’re all set up and have the proper tools, it’s time to take the clutch off the bike. The clutch cover is on the right side of the engine, and most covers have about 5 bolts holding it on (This bike is an ’01 Honda CR125).

After you get the cover off, you’ll be able to see the basket/plates. There’s five more bolts holding them together. This is where you may need a special tool to hold the clutch to prevent it from spinning while loosening the bolts. If you don’t have one, a cordless impact can be very handy to get it off, although you’ll want something to properly torque it back down.

CR125 Clutch Hub
CR125 Clutch Hub

All of the disks and plates will come out with the pressure plate. This is when you need to check the basket for wear/notching. It will be pretty clear if there’s notches from the disks. This basket does not have notching or appear to be broken, so it can stay right where it’s at!

CR125 Clutch Basket
CR125 Clutch Basket

Next we can measure the springs and plates to see what’s in spec. Refer to your OEM manufacture’s manual for minimum length on the clutch springs and minimum thickness of the metal plates. The min. length of each spring for the CR125 is 35.2mm (1.386″). I measured mine with a dial caliper and it read about 1.430″ (36.2mm), so they’re still within spec.

Measuring Clutch Spring
Measuring Clutch Spring

Next you can measure the metal plates. If they’re still in spec, feel free to use them as long as they don’t show signs of overheating (discoloration). I just bought a complete kit for this bike, so I’m putting in all new plates and disks. Sometimes you can just get away with replacing the fibers/friction plates since they usually wear out faster.

Most clutch plates you will have to soak in oil prior to putting them back on the bike. If you start and run the bike with them dry, you’ll greatly increase your chances of breaking or damaging the clutch. I just take bucket, pour a little engine oil in, and one-by-one place each plate and disk in, swirling the oil around so it covers all of them.

Soak Plates/Disks In Oil
Soak Plates/Disks In Oil

Now you’re ready to put them back in. You’ll start with a friction plate, and alternate until they’re all in. There’s one more friction plate than metal disk, so you’ll start and end with one.

 

CR125 Clutch - Friction Plate
CR125 Clutch – Friction Plate

 

CR125 Clutch - Metal Disk
CR125 Clutch – Metal Disk

After the plates and disks, it’s time to put the pressure plate and springs in. Now you’ll need something to hold the clutch assembly again so you can torque down the bolts. Again, check your service manual for proper torque specs. This CR125 requires 7 ft. lbs. for the pressure plate bolts.

All that’s left is to put the cover back on and fill ‘er back up with oil! Before starting the bike, pull in the clutch a few times and make sure everything feels right, like it’s disengaging and engaging. On the first start, warm the bike up properly┬áby letting it idle for at least a couple minutes. It’s not unusual for the clutch to drag at first; it just needs to be broken in.

Once the bike is warm, ride the bike around for a few minutes to make sure everything is still functioning. After that, you’re good to go! I recommend changing the oil after a few hours of riding if not sooner to get rid of any shavings from the new engine parts.

Click Here To Buy My Clutch Kit!

-Tom Stark

2002 Honda CR125R Review

For those of you dirt bikers that would like to know a little bit about the Honda CR125, tune in to this post as I will give you a review of the bike. Although it is a 2002, not much changed since 2007 except that the motor was modified a little bit in 2005. So this should be pretty accurate to the newer models as well because Honda pretty gave up on their two-strokes once they unleashed the thumpers (four-strokes).

2002 Honda CR125R

 

Comfort

First off, I wanted to mention the comfort level on this bike is excellent. It’s probably the tallest bike I’ve ridden, seat height-wise, but it’s also one of the most comfortable motocross bikes I’ve ridden. It’s a little bit high for shorter riders like me(5’6”), but once you get on it it’s fine.

Suspension

For being stock suspension, I thought that it was great. Although I did not ride it extremely hard, it worked out very well for me. It soaked up all the bad landings, the braking bumps did not throw me around, and in the corners it wasn’t wanting to stand up. Since I am a lighter rider I thought the stock set-up would be a little on the stiff side, but I turned the compression and rebound clickers on the forks and shock all the way in and it was fine.

’02 CR125R

Engine

Now you may have heard that the Honda two-stroke enginessuck, they have no power, and they are the worst two-stroke ever. If you did not hear that, then disregard what I just said. Now, some of that is partly true. They don’t have the most powerful engine that’s for sure. But that’s not to say that they are slow. After all, it’s mainly the rider and not the bike, but we’re not here to talk about that. As for the power, yes the bottom-end is very weak. In fact, it’s so weak that it’s surprising that it even goes. Once you get it into the mid-range then it wakes up a little bit with okay power. The top-end hit isn’t the most powerful in it’s class either, but it’s nothing to be ashamed of. The motor also has the “Rattle of Death,” I have heard, and my CR had a rattle too, but you shouldn’t need to worry about that because pretty much all of them have it.

Handling

Handling on this bike is probably number one in it’s class. It can go through corners faster than you are able to! Wait, does that make sense?? Anyway, the handling is great much like the stock suspension. This is probably the biggest reason why people buy Honda’s, and I agree with them; it’s great!

Jetting

The jetting on Honda’s is one thing that scares people away. The two-strokes tend to eat up spark plugs quickly if the bike isn’t jetted for the correct temperature and altitude. I didn’t have any problems with mine because I bought it with it correctly jetted for where I ride. I am not an expert with carburetors, so I suggest bring it to a trusted mechanic and get it properly jetted. If you want to do it yourself then buy a manual for the bike if you don’t have one already and read it carefully. Don’t let the Honda jetting or rumors about it always being hungry scare you away. It’s a great bike. You just have to fix the carburetor right way. Unless of course you go with the PWK Air Striker like many people are doing.

What I Think of It…..

Overall this is a great package for new riders. It looks great, it rides great, and two-strokes are easier/cheaper on maintenance. This is a perfect bike for a new racer that doesn’t need much power and wants a good handling, stock bike. After the the jetting is fixed, you got a great bike in your hands. Make sure you maintain it, have fun, and keep those two-smokes rollin’!!

-Tom Stark

Riding the Honda CR125R: