Project Yamaha TTR230 - Part 1 - Dirt bike suspension, power and handling

Modifying the ""Other"" 230 Electric Start Bike

Jul. 01, 2007 By Rick Sieman
We’ve been doing our Project Honda CRF230 for quite some time now. In that time, we’ve improved the suspension, power, traction and handling dramatically.  It comes as no surprise then, that the owners of the Honda’s counterpart, the Yamaha TTR 230, let us know that they were being left out.
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Yamaha TTR230T

Since both the Honda and the Yamaha have been virtually unchanged since 2005, the modifications that have been done, and will be done, apply to the 2005, 2006 and 2007 models.  We acquired a 2005 Yamaha TTR 230 with only a few hours on it.  It was barely broken in, and more importantly, was completely stock.

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Electric starter button

Both these bikes are designed are beginners/ladies/fun trail bikes. They have electric start, which makes the ideal for the older rider who just wasn’t want to deal with the hassle of kicking a bike over.  More importantly, they’re ultra-reliable, air-cooled bikes that are inexpensive to buy and maintain. And when it comes time for a rebuild, instead of spending thousands, you’re talking hundreds.

What will a TTR 230 cost you?  Well, you can get a brand new 2007 for the suggested retail of around $3400, plus tax and title. Or you can a new (unsold) 2006 from many dealers for around $2500, or less if you shop around.  Your third option … and the one we chose … was to buy a very lightly used 2005 model for around two grand.  You should have no trouble finding a very nice 2005 model, in that many of them are bought for wives or girlfriends, who simply didn’t ride them much.

Add to the fact that the bikes can be made worlds better with a bit of tuning and modification, and you end up with a sensible project.  No two hundred dollar sticker jobs, thousand dollar titanium pipes or multi-thousand dollar suspension pieces.  Just sensible, affordable modifications that you can do, with step-by-step photos and captions.       

Let’s take a look at the Yamaha 230 to see what we’re dealing with:

Key Features:

  • YZ looks, and a 223cc air-cooled, SOHC four-stroke single. 
  • Competition style flat seat/tank junction.
  • Electric start.
  • A low seat height with reasonable travel suspension and 12 inches of ground clearance.
  • Steel, diamond-type frame.


  • Super-reliable, electric-start 223cc air-cooled SOHC four-stroke puts out smooth, widespread power.
  • Six-speed transmission.
  • CDI magneto ignition system is reliable and nearly maintenance-free.
  • YZ-type air filter for easy maintenance and maximum airflow.
  • Automatic cam chain tensioner means minimal maintenance and longer engine life.


  • Compact wheelbase and low seat height.
  • Linkage-mounted rear shock with 8.7 inches of rear wheel travel.
  • 36mm front fork with 9.4 inches of wheel travel.
  • 12 inches of ground clearance.
  • Aluminum box-section swingarm features snail-type chain adjusters for quick and easy chain adjustments.
  • Front 220mm disc and 130mm rear drum brakes.
  • Full-size 21-inch front and 18-inch rear aluminum wheels with knobby tires.

 Additional Features:

  • Long seat is low and allows easy rider movement.
  • Team Yamaha-inspired colors and graphics.
  • 2.1-gallon capacity for good range.
  • Large, folding cleated footpegs.
  • Durable fork boots provide excellent fork seal and stanchion tube protection.

MSRP*$3,449 (Team Yamaha Blue/White) 
Engine Type … 223cc air-cooled, SOHC, 4-stroke single
Bore x Stroke … 70mm x 58mm
Compression Ratio … 9.5:1
Carburetion … 26mm Teikei
Ignition … CDI
Transmission … 6-speed w/manual clutch
Final Drive …Chain
Front Suspension…36mm telescopic fork; 9.4" travel
Suspension/Rear … Link-type single shock; 8.7" travel
Brakes/Front … 220mm Disc
Brakes/Rear … 130mm Drum
Tires/Front … 80/100-21 Pirelli MT320H
Tires/Rear … 100/100-18 Pirelli MT320
Length … 81.3"
Width … 31.5"
Height … 46.5"
Seat Height … 34.3"
Wheelbase … 54.5"
Ground Clearance … 12"
Dry Weight … 24 lb
Fuel Capacity … 2.1 gal.



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Here's our TTR230, before modifications

Naturally, we were curious as to how the Yamaha performed in stock trim.  And, importantly, how it compared to a stock Honda CRF230F. 

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Teikei is 26 mm and needs rejetting if the intake and exhaust are modified

Starting the Yamaha is easier that the Honda.  There’s no key to screw around with;  just push the “on” button in the center of the top triple clamp, pull out the choke (left side of the carb) and hit the start button on the right side of the handlebars.  There’s also a kill button on the left side of the bars.

The engine comes to life immediately and as it warms up, you can put the choke in a bit to keep the motor from stumbling from a too-rich mixture.  Unlike the Honda, which takes forever to warm up properly, the Yamaha is ready to ride in a few minutes of warm up.

When you first get under way, you can tell that the gearing is ludicrously off, just like the Honda. Low gear is absurd.  You can almost walk alongside the bike in low.  A shift to second shows that it’s very close to first; it’s only when you get to third gear that the motorcycle starts to feel right.  In third, the Yamaha will easily pull from five miles per hour and rev out nicely.

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Our first change will be the gearing, as both a 14 and 15 countershaft sprocket will be tried

I’ve read many reports of people who have dropped from the 13 tooth countershaft sprocket to a 12, claiming that it helps in the tight stuff.  This is quite possibly the dumbest thing you could do to the bike.  We plan to go up one and two teeth on the countershaft sprocket, to see which one works the best in a stock and modified bike.  The order is already in to Sidewinder for those sprockets.

The Yamaha seems to have a better spread of power than the Honda.  It pulls good down low and seems to rev out a bit more, where the Honda flattens out.  We’ll know more when the bike is geared more sensibly.  One thing that stands out on the Yamaha is the  smoother throttle response at low rpms.  With the Honda, when making a tight turn, the throttle response was jerky at low revs.  So much so, that it was easier to ride the Honda a gear higher than normal and slip the clutch. The Honda does seem to have a touch more mid range than the Yamaha.

Suspension-wise, the Yamaha seems to be a bit softer and more plush than the Honda, but when hitting small square-edged bumps,  the shortcomings of the forks become more apparent.  On bigger bumps, both bikes quickly show their flaws and the rider is forced to re-think what the limits are.  The rear end of the Yamaha is better than the front end.

Handling on the Yamaha is fine, considering the limitations of the stock Pirelli tires, which are marginal on anything hard-packed or in sand.  They work OK when traction is perfect, but then, what doesn’t?

Shifting is just fine, the front brake is excellent and the rear brake is world’s better than the Honda.  When you ride the Yamaha, you can’t feel the 15 pounds of extra weight.

Oddly enough, the smallish rear wheel brake setup, which is similar to the Honda, works worlds better. Very, very strange.

The stickers on the tank wings are trash, pure and simple.  Printed on cheap paper-like material, the color rubs off them in no time, making the Yamaha look old before its time.  We plan to do something about them;  at the very least, remove the stickers. 

You notice right away that the Yamaha has less ground clearance than the Yamaha, which also translates into a bit less saddle height. Newsletter
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