FLAT RATE $11 EXPRESS SHIPPING ON MOST PARTS ORDERS.

Yamaha YZ

  YZ250

YZ85 Suggestions:

Great bike but lacks bottom end power as it doesnt have a powervalve like most of the competition. This isnt an issue for expert riders but can make it harder to ride for beginners. Best mods are setting up the head and broadening the spread of power with mods to the cylinder.

GREEN is the minimum we suggest for this model
RED is our top pick for trail/enduro
BLUE is our top pick for MX

Gains Mods
Package 1 Bottom-Mid-Top Setup head Buy Now
Package 2 Bottom – Mid Setup head + machine cylinder base Buy Now
Package 3 Everywhere Setup head + standard porting Buy Now
Package 4 Everywhere Setup head + advanced porting + machine cylinder base Buy Now

 

YZ125 Suggestions:

Great engine for a 125. Doesnt quite match the KTM up top but its makes a great spread of power for a 125. Suffers from detonation damage to the head and cylinder due to the head design. Best solution of to setup the head properly and make sure its installed perfectly centred on the cylinder. Top end life is much better after doing this. Stock jetting needs some attention even if you keep the engine in stock form.

Big bore 144cc setups are a good option for much better power bottom-top. The Athena 144 kit is great value for money for trail riders but for more serious riders or racing of any kind the porting specs and head design limit power on these kits. A much better option is one of our own TSP 144cc big bore kits. We can match the head and porting specs to suit your needs and do all of the modification work in-house. Contact us for more info.

GREEN is the minimum we suggest for this model
RED is our top pick for trail/enduro
BLUE is our top pick for MX

Gains Mods
Package 1 Bottom-Mid Setup head Buy Now
Package 2 Everywhere Setup head + machine cylinder base Buy Now
Package 3 Everywhere Setup head + standard porting Buy Now
Package 4 Everywhere, especially mid-top Setup head +  Advanced porting Buy Now

 

YZ250 Suggestions:

Another great engine from Yamaha that has stood the test of time. Makes good power in stock form but its very prone to detonation and poor top end life when ridden hard due to the head design… as a result they must be jetted very rich to keep temps down. Best mod is to setup the head properly. Once this is done jetting can be safely made leaner and it will make more power everywhere. Our lower comp head design makes more power than a stock bike everywhere from idle up to around 51rwhp at peak when matched with an FMF pipe. A stock engine is approx 48rwhp with stock pipe. No need to do extensive porting as the cylinder produces good enough power for most riders.

Big bore kits are another option. The Athena 295cc kit is great value for money for trail riders but the head design and porting specs limit power a lot… the Athena kit makes way less power up top than a stock 250 with basic mods, it is very strong down low though, however the very high compression Athena head requires very rich jetting and makes the engine quite aggressive. For racers or more serious riders we suggest one of our own TSP 265cc or 295cc big bore kits. We do all the modification work to your existing 250 top end in-house and can tailor the head setup and porting specs top your needs.

GREEN is the minimum we suggest for this model
RED is our top pick for trail/enduro
BLUE is our top pick for MX

Gains Mods
Package 1 Bottom-Mid-Top Setup head Buy Now
Package 2 Everywhere Setup head + V Force reedcage Buy Now
Package 3 Everywhere Setup head + standard porting + V Force reedcage +FMF pipe Buy Now
Package 4 Everywhere, esp mid-top. Setup head + advanced porting  + V Force reedcage Buy Now

Or combine your own package of mods:

Mod Gains Price
Head Setup  Everywhere, plus reliability  $260
Standard Porting  Everywhere  $240
Advanced Porting  Everywhere, esp mid-top  $350-$400
Carb Oval Bore  Mid-top  $250
Dyno Tuning  Everywhere, plus reliability  $350 for first 3 hours
V Force reedcage  Everywhere, plus throttle response  $175-$200 approx
Big Bore kit  Everywhere, esp bottom-mid  $1200-$1500 approx
Cylinder base machining  Bottom-mid, often slight loss of top  $110
Specialist Labour  Get us to rebuild and tune your engine  $110/hr