Jump to content
Sign in to follow this  

YZ125 upgrade ideas!?

Recommended Posts

I currently have a 2005 YZ125. I race as well, and I'm looking to upgrade a little. My bike has a full ProCircuit exhaust with a Factory 304 not the shorty. My suspension is good, I weigh around 145-150lbs with gear. Should I get valving done to my bike? Big Bore? Bolt on parts?

Share this post


Link to post
Share on other sites

Make sure you jet for the pipe you get, and for some bling upgrades youcould buy spokeskons for $30, they made my bike look much nicer

Share this post


Link to post
Share on other sites

What kind of racing?  A big bore will be illegal for many MX classes, but fine (and useful) for offroad racing.

 

Obviously quality practice time is the most important upgrade.  After that, for most racers, I would rank things as follows in terms of "bang for the buck":

1. Fresh tires.

2. Fresh tires.

3. Fresh tires.

4. A "knobby knife" to keep a good edge on your tires

5. Learning how to adjust tire pressure and suspension clickers for track conditions.

6. Suspension (only if you weight or speed falls outside the design parameters of the bike)

7.Keeping your bike it good working order to prevent safety issues and DNFs.

8. Power mods

 

I rank power mods (pipes, reeds, and all that kind of stuff) lowest, simply because it usually does not have any effect on lap times.  Most guys just end up shutting the throttle faster when given more power, and end up going the same speed.  Now of course it could be a different story if a power mod allows you to consistently clear a jump you could not do otherwise, but that seldom happens in real life.  Also, major power mods (like a big bore), if legal, could be useful in certain conditions.  

Edited by rpt50
  • Like 1

Share this post


Link to post
Share on other sites

Tossing that PC pipe in the trash not a good pipe design for this bike there is an older post on here comparing the pipes.

Share this post


Link to post
Share on other sites

I like my pc over fmf or the factory header,  Carbon tech reeds work realy well and a 2mm bore with porting realy helps these bikes. If you know alot about engines and want to spend money a 144 stroker is amazing but over most peoples heads. :thumbsup:

Share this post


Link to post
Share on other sites

The PC pipe sucks they thought they could out think Yamaha and added a dumb hook in the header pipe their idea was. That the stock pipe lacked header length and they built an old school pipe with a hook design in the header. They succeeded in creating a pipe the kills the bottom end and flattened the mid and it hits hard on the top end would be cool if it made more horse power over stock but it doesn't.

The older posts I speak of have dyno runs showing that is the case so unless you want a pipe that hits hard on top only and flattens the rest of the power curve the PC is good vs stock it sucks. The stock header with the straight flowing header is a much better design even PC older pipe for the older motor has a straight header pipe design.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

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

Reply with:

Sign in to follow this  

×