Making the throttle light as it should be

One of the things I didnt like on the Xtrainer is the hard throttle pull.
In normal riding condition its not so bad, but when negotiating super technical obstacles or when you need the last bit of traction, precise throttle control is required and the hard pull won't help.

Trying to understand the source of the problem, I tried first to re-route the throttle cable. Didn't help any, even when (for the sake of the test) I had it completely straight.

Taking routing out of the question I have been left with one option only - the TPS lever return spring!

Compering to the buttery smooth any EU 2S bike with Domino throttle, the Xtrainer (and starting in  2016, the 250/300 RR's as well) equipped with a different version of the Keihin PWK carburetor. This version have a TPS (Throttle Position Sensor) installed, together with a leading arm which is spring pre-loaded forcing the TPS arm against the slide to eliminate hanging.
The problem is that Keihin left the same PWK spring in place, and the hard pull caused by the added resistance of both springs together.

9$ later, I bought another PWK spring and trimmed about 1/3 of the length. Install it back in (trimmed side up) and VOILA! smooth and easy as it should be :)

Now I got it right!
I did a custom made throttle springs, softer than the original and throttle pull went to where it should be. Got some extra if some interested! :)

Parts parts parts...

OEM replacement parts, compatible with other manufacturers

Nissin front brake lever
It's same as older models of Honda. Include CR80/85 98-07, CR125/250 84-07, CRF150/230 04-07, CRF250-450 02-06, CR250/400R 96-03, XR650R 00-04

Brembo clutch lever

Basically it's a the same as KTM Brembo clutch lever from any year. 

Rear LED light
Same as CRFX tail light. Just need to wire up the old connector.

Spark plug
NGK BPR7EIX is a direct replacement for the OEM / Beta only cat. number.

Brakes

Those are compatible with zillion jap bikes. Just to name few

Front EBC Sinter pads MXS185

• Honda CR125R / CR250R 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007


• Honda CRF230 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011


• Honda CRF250R/X 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011


• Honda CRF450R/X 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011


• Honda XR600R 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000

Rear EBC Sinter pads MXS367

• Kawasaki KX250F 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011


• Kawasaki KLX450F 2008, 2009, 2010, 2011


• Kawasaki KX450F 2006, 2007, 2008, 2009, 2010, 2011


• Suzuki RM-Z250 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011


• Suzuki RM-Z450 2005, 2006, 2007, 2008, 2009, 2010, 2011


• Yamaha YZ125 / YZ250 / YZ250F / YZ450F 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011


• Yamaha WR250F / WR450F 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011

Power! More is better!

Last week, riding some extreme trails in Couger Buttes in the SoCal high desert, I was not too happy.
The power was just not enough for what I wanted. I wanted more off idle so it will help me to lift the front to pivot turns or to challenge rocks with zero approach. I want some more in the middle so I can lift the front over obstacles easier. I want more revs so I can use more of each gear and to avoid going flat in long hills. Basically I want more everywhere!

For many years I have been riding KTM 300 which I thought have the best engine in the business. Last July I had the chance to try 300RR and my jaws dropped! Even better than the already perfect KTM engine? I was sure it was impossible!

So buying the Xtrainer which basically has a tuned down RR300 engine would give even better low end, at least that was my expectation. This is why I was disappointed a bit from this "nummy" engine.


1st thing to do was to wind out the power valve adjuster. That helped some in the middle as the bike picks up RPM's faster. Still sleepy low end.

2nd I removed the power valve spacer which effects the overall volume of the pipe.
Good results, the bottom end woke up some! All you need for this small mod is 4 M5 screws 10mm shorter and 1 minute of your time.

But I wanted more! :)

I borrowed from a friend an FMF Gnarly pipe to try. The good news was that it bolts right up. Perfect clearance everywhere from the frame, cooling houses and shock.
The great news was that it was just it! The bike picked up horses everywhere from bottom end to very nice over rev. It's not RR yet but it's just perfect for this bike and actually I winded back the power valve adjuster almost a complete turn to calm it down a bit.
Roll on drag race from 2nd gear against 250RR and they are bike to bike up to par without any problems.

One important word for anyone that want to use this pipe and does not have experience with 300's - Buy a slow throttle like the G2 Dirt tamer to get better control and secondly, wind the power valve adjuster at least 2 turn in from flush.

 Last but not least, I want to thank Dave from Get Dirty Beta dealership in Morongo Valley CA. Great guy, great rider and excellent dealership!
He can fix you with any Beta item you can think of and said to be cheaper than direct purchase from Beta USA site.

And the results? Not bad I think! :)