Comparing 00, 01, and 02 v-force for cr125.

[NO HAND]

I had a chance to have both reed cages on hand; the 01 and 02. What happens is: the 01 has an offset rear opening that has to go with the 01 manifold also. It cannot interchange with other years' manifold. The 02 reed cage has a central rear opening that is overall smaller than the 01 model. It is made to fit the smaller manifold on the 02 model.There used to be a 00 model availlable that had a central opening but with the larger diameter than 02. Now the model is discontinued and 00 owners have to use the more restricted 02 model. What would be the ultimate combo availlable for now is the 01 manifold with the 01 cage. If you have a 00 or previous years, you would have to buy the 02 model and hog it out to fit your manifold.

 

[marcusgunby]

Good info No Hand -how far are you from building up your ultimate red machine??

 

[NO HAND]

I can't wait to get all this together. 133 mid-top cyl, 02 vforce hogged out to fit the 99 manif, 01cr250 airbox, 40mm sucker on the quick pull cable. Not to forget the very trick shortened silencer to marcusgunby specs :) I'll need some time to test each mod individually so I can differentiate what gives what. I kept the stock 36 carb attached to the stock 00 cage so I can swap. I wan't to be able to tell if that 40mm is a good idea or not. As soon as I get the jug you bet you'll hear about it!! It won't be a 125 SX but at least I hope to keep up with my 133 KX friends.;). Here the track isn't rideable anymore(rain+mud+freezing temp) :( . You guys ride for me please. :confused:

 

[NO HAND]

Concerning the V-Force cages. I have a friend who just bought a v-force cage for a 95. It happens to be the same model as we use on the 02 cr125, and I noticed that the rear opening of his cage has been changed compared to mine. His cage has a bigger rear opening to match the bigger manifolds. I think V-force has just changed it to accomodate those who switch to a older manifold for a mid-top powerband. If I had this one, I wouldn't have to hog it out.

 

[marcusgunby]

Seb i just modified my 02 rubber manifold to match up with the 01 vforce-the 02 rubber manilfold has an unbelievably small opening.-its like its off a KX65-it didnt take much work to modify the 02 manifold.Now a friend has a 02 manifold and a old style 00 v force-i had to cut loads out of the rubber mainfold to get it to be a smooth transition-the new hole was almost twice the original size. I guess his might have more overev but less torque-we will see-our engines are bery similar apart from the different v force.On manifolds-the 02 reed manifold accepts a Kehin carb with no problem(unlike the 01) but the back side of the carb is a couple of mm bigger, and its a tight fit into the airbox boot but it does go in.The Kehin carb is also 75mm from front to back and the mikuni only 60mm so i may have to remove the reed spacer that comes on the 02(5mm spacer) to fit the Kehin when i decide to try it.

 

[ryan]

No Hand mentioned his shortened silencer, want to know if anyone can give me the specs on what length to cut the silencer off? Do you wield it back on or do you revit it back on? Just wanted to know cause I am in the process of changing alot of stuff on my bike (01 CR 125). Another thing, I had my good friend look at my cylinder about porting it, he used to build his own banshee racing motors) he said that there wasn't really much he could do to it w/o killing the bottom end because it looks pretty radical from the factory. Can anyone give me any hints about porting my bike. I was thinking about adding epoxy to the transfers to give it a little more bottom end, but not sure about it. Any help is appreciated!:)

 

[Jay-R]

There is an entire thread on shortening of CR silencers, but I could not find it. Anyway, drill out the rivets, take it apart and cut 50mm off of the back of the shell, then cut 50mm off the front of the core. Put it back together and rivet the end back on. It works pretty well, makes for a little more response on the bottom end. Mine didn't seem any louder either.

 

[NO HAND]

Ryan, With those two links you should be able to find more than you need. Jay-R has it right with the silencer. Jay, I'm glad to find it is not much louder:D
Marcus, Was it hard to match the offset v-force back plate to the centered 02 manifold? Did you have to hog out the cage back plate or just the manif? When I matched my 99 manifold to the 02 v-force I dismanteled the v-force back plate to let me see how much I had to remove from inside the cage and mark the lines. I also found that the manifold was easier to work on if I had put it in the freezer before. The rubber is easier to cut and leaves a smooth finish.
(link 1)
(link 2)

 

[whyzee]

Cutting stock silencer

Hey Jay & No hand,
What do you think the low end effect would be on a yz125, been thinking about a fatty and a shorty as soon as I get my top end back from Eric, but what with i'll owe Eric plus new clutch, chain, and replacing just about everything else that is tired and worn on the bike, Maybe i'll save the $250.00 for food and cut my stock silencer.?!
Dave

 

[Jay-R]

I haven't seen anything on cutting a YZ silencer. So I don't know how much to cut, or if it will really help. But, you could look at an aftermarket shorty to get some measurements to go by.

The main reason that I cut mine (besides to get more power and save money) was that I thought the aftermarket shortys were too loud. I am very pleased that mine seems no louder than stock (could be that really good pink insulation that I packed it with).:D

If you do cut it, let us know how it worked, my buddy has a '01 YZ 125 and has been debating cutting his.

 

[whyzee]

think i'll wait. want to see the true response of Eric's work before i tinker any more. If this thing is the rocket I expect it to be, i may rejet a bit and leave it alone.

Thanks for responding and let me know if your buddy makes the modification.
Dave

(I just read what I wrote) Leave it alone, HA HA, what was I thinking.

 

[marcusgunby]

Seb we will be talking about this mod when were 40 years old:confused: the 02 manifold is a close match to the 01 v force-one side lines up and the top, bottom and other side need to be opened but not much.I like your idea if putting the manifold in the frezzer-i wish i did that.I too removed the plate from the v force to act as a template-marked the manifold and used a grinding stone in a drill-it took about 15mins.Smoothed it afterwards with some sandpaper.