Yz 125 exhaust?

Hi i got a 125 a few months ago and iI plan to ride it on the trails mainly and i will do a little motorcross. The pipe i currently have is a procircuit platnum and is great in the middle and top end. I know these bikes arnt made for bottom end but can i get a pipe to help it for this?

Thanks

On a '05+ YZ125, the stock pipe or FMF Fatty is better suited for a lower/wider power spread.

A fresh top end and careful attention to jetting also helps in getting the most out of the lower rpms.

Edited by mlatour

FMF Fatty will give you a bit more bottom to mid but sacrifices a bit of top. I ride woods and track with it on my CR and it's done well. However having the bike properly jetted should give you gains all over, that's what made the biggest difference for me. So start there (JD Jet kits are nice too).

Okidokie i know the bike is slightly rich but its not fowling plugs im just scared of leaning it out to much that i will cease it i run at 50:1 on motul 800 how can i get sign that it is to lean before it blows up

Okidokie i know the bike is slightly rich but its not fowling plugs im just scared of leaning it out to much that i will cease it i run at 50:1 on motul 800 how can i get sign that it is to lean before it blows up

Install a new plug and do a full throttle run down a field from 1st to 5th (or 6th) gear. Pull the clutch in and kill the bike and coast to a stop. Pull the plug and look at the tip for a colour reading. White/Grey is too lean. Black is too rich. You want chocolate brown.

Ok thanks its nearly due for a rebuild but i might also get that fatty

Thanks for the help

You should never run a 125 at 50:1. Read your manual. The bike comes jetted for 30:1 (or 32:1) so that's what you should be running unless you re jet for a different ratio. You will surprised at how much better the bike runs with 32:1.

Pipes are not going to make much difference in low end. You will get much more bang for your buck with gearing changes. Add a tooth or two to the rear sprocket. However, the simplest cure (and cheapest--free) for the 125 low end is to stay out of it. Practice two things:

1. Whatever gear you think you should be in, go one gear lower,and wring that little engine out!

2. mercilessly and relentlessly abuse the clutch. Whenever the revs fall, light the engine back up by clutch slipping.

Edited by rpt50

And the usual thing for any 2 stroke MX bike being used in the woods, a FWW. Stick a 9-11oz Steahly (http://www.steahlyoffroad.com/) on there and it will do far more for woods lugging than the Fatty pipe alone can dream of, and at half the price. Combine the FWW with the Fatty and a VForce 3 reed block, and you'll have a mean little woods ripper that will lug down like you would never think a 125 ever could.  :thumbsup:

Ok thanks sorry for the extremely late reply i will try a tank of fuel at 40:1, will that be ok? Ill have a look at the stealthy

 

Thanks

Edited by Max.J331

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now