1. Use low-smoke 2T oil, like this one from Petronas; Petronas Sprinta 5000 2T 2-Stroke Full Synthetic.

2. Never mix different brand of 2T oil. For example, if you use Petronas Sprinta 5000, stick for it for the rest of the life of the bike. It is also okay if you stick with cheap 2T oil, as long as you don’t mix them up, you will get less smoke.

3. Adjust the 2T pump on your bike throttle cable. This will reduce the amount of the 2T that gets into the combustion, so you will get less smoke. Here you need to remember that when you reduce the amount of 2T oil that gets into your engine, you also minimise the lubricality of the engine. So, if you want to use your bike for heavy use (eg: racing), adjust the setting so that more 2T oil can be pumped to your engine.

4. Check, service and adjust your carburetor for maximum fuel and air mixture for combustion, as this one will make your combustion chamber cleaner and therefore produce less smoke.

5. Use your bike at optimum RPM. Your exhaust will form a resonance inside the exhaust chamber to produce back pressure and back pressure can give more fuel, air and 2T oil to be combusted back into the engine.

Any more idea? Share with us in the comments section.

Why do you need to use racing chamber exhaust?

The basic idea behind an expansion chamber is to use the momentum and pressure of the exhaust gases to create a pump that squeezes more air and fuel into the cylinder during the intake stroke. It does the same sort of thing that a turbocharger does, but it does it without moving parts.

If you have read How Two-stroke Engines Work, then you know that the exhaust and intake parts of the cycle overlap. As the piston moves down, it uncovers the exhaust port first to let most of the exhaust out. Then it opens the intake port to let fuel/oil/air in. With a correctly-tuned expansion chamber in place, two things happen to help the intake process:

• As the exhaust gases expand into the expansion chamber, they create a vacuum at the exhaust port. This vacuum pulls fuel/oil/air into the cylinder.
• As the shock wave of the exhaust pulse hits the end of the expansion chamber, it echoes back, pushing any fuel/oil/air that got pulled through the exhaust port back into the cylinder. This page has a nice graphic that describes the process.

By pulling extra fuel/oil/air through the cylinder and then pushing it back in, the expansion port has the effect of stuffing more fuel/oil/air into the cylinder on each stroke. This gives the engine extra power in the same way that a turbocharger does.

Here are some interesting links:

• How Two-stroke Engines Work
• How Turbochargers Work
• Building your own racing Expansion Chambers
• Exhaust Pipe “Theory”
• Tuned Pipes

The new Yamaha RX-Z Malaysia Group has been setup in Google Groups for all us to share anything about Yamaha RX-Z 135 bike.

Posting in English and Malay are accepted.

Don’t just read, REGISTER NOW at http://groups.google.com.my/group/yamaha-rx-z-malaysia?hl=en

Yamaha RX-Z carburetor

Total votes: 117

The poll have shown that Malaysian prefers Yamaha RX-Z more than 125Z, but LC135 is now the second choice after RX-Z. The least bike preferred is FZ-150i, this may due to the design of the bike that is not compelling and futuristic enough like the rest.

Keep voting for the new poll! Look for it at the right sidebar.

The Doctor’s bike that gives us the mean 125ZR 46 Limited Edition:

Hit the links here:
http://www.yamaha-motor.co.jp/global/race/2006motogp_review/history/index.html

The current design of Yamaha 125ZR since 2007. The design of the bike is nice, simple and macho enough. It was debut in 1999 with the first generation of 125Z and later followed up with 125ZR, which better and meaner.

At that time, there is no bike in the category that can compete with the bike. It was the era of Suzuki Best, Suzuki RG Sports, Yamaha SS, SS Two and Kawasaki K1, but none of the bike make a very deep impact like 125Z does. 125Z makes every other bike in the category seems like child plays. The technology offered by 125Z is far superior than what the people were thinking at that time and Yamaha was ahead in others in thinking of future of underbone bike.

I like this bike not because I want to rem pit, but I like what this bike has to offer.
You see, this is the only bike in the category that have monoshock suspension, front and rear disc brake, 6-speed gear, futuristic design and affordable!

Also, this bike is really fast. In standard condition, it can go up to 160km/h, tune the exhaust a bit, it’ll go up to 180km/h, tune it a little bit more, then you can’t measure the speed anymore since the meter is maxed at 180km/h!
I have heard that this bike can be tune to get 180 km/h just in the fourth gear.

Safety will become a thing to think here. Enjoy the speed only in the track. Not in public highway. Drive safely and be smart!

Also watch out for:
http://motomalaya.blogspot.com/2008/03/yamaha-125z-200607-catalogue.html

(Use colour #3 Silver or #39 Sparkling Silver as base coat for CANDYTONE colours to obtain best performance and shine.)

The colour here is just for guidelines only since the original colour might have been distorted due to different scanner colour rendering.

I would also like to thanks to SAMURAI paint for providing the colour card for this blogs. More info about how to paint motorcycles in future posts. Keep coming!

For more info about SAMURAI Paint, click here.

I spotted this on YouTube. The modification of this RX-Z really amazes me because it have rear disc brake, but not an ordinary disc brake, this one is installed on the left side of the bike where sprocket and drive chain is also installed!
Wow, I was just thinking to change my RX-Z rear disc brake using 125Z brake, but then, it can be installed on the right side like original brake placement for 125Z.
So, how can this be possible to install rear disc brake on the left side of the RX-Z?
Tell me us how in the comments box.
For the original content of the video, click here.

UPDATE: Rear disc brake modification for Honda EX5. Maybe you can use the idea from here and transferred it to your RX-Z project.

Check out other Yamaha motor catalogue:
Yamaha FZ-150i 2008 Catalogue
Yamaha RX-Z 2007 Catalogue
Yamaha RX-Z 2002 Catalogue
Yamaha LC135 2007 Catalogue

Price for 125Z is RM6300 and 125ZR at RM6620. All price is OTR.
For more Yamaha motor prices, click here.

Yamaha LC135 (Auto Clutch) 2007. Price is estimated RM6400 (OTR). Pricelist is here: https://www.bikesrepublic.com/category/pricelist/

Check out other Yamaha motor catalogue:
Yamaha FZ-150i 2008 Catalogue
Yamaha RX-Z 2007 Catalogue
Yamaha RX-Z 2002 Catalogue

Coming soon:
Yamaha LC135 Extreme Spirit 2007 Catalogue
Yamaha 125Z 2007 Catalogue. POSTED: Click here

Keep this link in your bookmarks or subscribe to RSS feeds to get the updates.

Looking to tune your carburetor by yourself? Want to check how LC135 throttle sensor is assembled?
You can get it at yamahat135.com but you need to register first.

Need this parts catalogue?
This is not for Yamaha 125Z, but for Yamaha YZ125S.