2001 CR 125 Jetting??

[Jay-R]

I was just wondering what jetting some of you are running in the 2001 CR125. I have done a search on it and haven't found anything.

Stock jetting is:

Needle- 6BEG20-68 3rd Groove
Pilot- 45
Main 380
Air Screw 2 1/4 turns out

MXA recommends this jetting:

Needle- 6BEG21-69 1st Groove
Pilot- 45 (stock)
Main- 380 (stock)
Air screw 1.5 turns out

Heres the catch, they recommend a 4.5 slide and the stock one is 5.0. I really don't know anything about cutting the slide, and I haven't found a different size to buy.

FMF recommends this jetting:

Needle- Stock 2nd groove
Pilot- 50
Main- 360/370
Air screw- 2.5 turns out
Slide- Stock

Heres the catch with FMF, they say that you need to run 50/50 mix of race/pump gas in the CR125.

I ride really close to sea level, using Motul 800 2T 3oz per gallon with 92 octane pump gas. Stock bike with 50mm cut of the silencer. The bike has very little spooge coming from the exhaust. I have been running stock jetting with the clip in the first position. The bike seems to have a hesitation right off the bottom. I was just wondering if anyone had jetting recommendations for summer and or winter. Summer temps here are 85 to 95 deg with high humidity. Winter temps here are 35 to 55 deg.

Thanks for your replies.

 

[marcusgunby]

Jay R I think if you bike runs reasonable well now i would move the clip down a notch on the needle and it should run better as its cold now i needs to be a bit richer.Ive heard of people using the 4.5(richer slide) than std but cant see how this helps.
FMFs reccomendation of 50/50 race/pump gas isnt a bad idea-the 01 CR is sometimes on the verge of detonation but if you have good pump gas you may be ok-how has the last piston looked like?Is the top edge kind of worn away and has little pin markes on the top of the piston?
A easy way round the detonation problem is to use 2 head gaskets.

Dont forget to rest the airscrew for the colder weathers and when altering needle clips.

 

[Jay-R]

Marcus, I am planning to replace my piston and ring for the first time in the next couple of weeks. Also, since it is winter, I am planning to raise the needle one position. I haven't attempted to adjust my airscrew yet. What is the typical adjustment when you change the needle postion? I believe that I will try 50/50 race gas, since the CR engine seems to rattle quite a bit.

Also, I know that the vertex race piston recommends race gas because of the increased compression. If I switch to this piston, could I use the thin cometic base gasket? Or, would this be too much compression. I know that this setup would require race gas.

I am going to order the V-force reed cage, which setting do recommend on this?

Thanks for the info,

Jay-R

 

[marcusgunby]

Jay to get the best results you should set the airscrew each ride but in reality once you get close it shouldnt need to be altered more than a quater of a turn.Whn you alter needle clips it can make a big difference.On the 02 my friend has when we fitted the piston and tailpipe i had to go in nearly a turn to get it to run right-that loose std piston i think was making the jetting funcky.When you put a vertex in it will not rattle at all.If you fitted the cometic gasket as well- just duuble up the head gaskets and with a 50/50 mix i think it will be o.k.

On the v force i left it in the std(high tension position) but if you are after bottomm end i would try the low tension setting.
Marcus.

 

[ryan]

I also have a 01 CR 125 and I just ordered a weisco piston kit. Just wondering if a weisco piston will cure the clearance problem on this bike?

 

[marcusgunby]

Ryan yes the wiseco is also a good choice.

 

[01HondaCR]

OK what would the jetting be for the 2001 CR with pipe and silencer. I use the highest grade pump gas and live about a half hour north of Indianapolis Indiana. So about average elevation for the midwest I suppose. Thanks.

 

[01HondaCR]

Come on someone has to know. I emailed Pro Circuit a few days ago and they havent emailed me back. I dont want to have to start a new thread just for this and I really want to get out there and ride.

 

[marcusgunby]

01 honda its very hard to say what jetting will work for a bike with certain mods at a certain elevation-start rich and jet leaner.Erics website www.eric-gorr.com has a good guide on how to jet by feel.