More Trail – Less Flail

I don’t know who came up with the term “more trail – less flail” or its sister term, “less trail –
more flail”, but both are brilliant in their simplicity. There are other factors involved when
it comes to what makes any given motorcycle steer a certain way like triple clamp and
fork off-set, rake, wheel base, center of gravity, overall weight etc.

If your heavy KLR650 spends its life on sticky pavement you can sometimes get along
with less rake and trail but conversely if your knobbies are in loose dirt and sand you
better have more of it.

I was once criticized for making negative comments about raising links when they
appeared on the market. The comment was “how can he criticize them if he hasn’t tried
them. With more than a quarter of a million miles on KLR650A models I learned long ago
that if you fix the upside down ride height problem with a Top Gun/MMP spring, you will
love the stock steering on pavement. That’s if your steering bearings aren’t loose (loose
bearings equals twitchy steering).

The KLR650A model stock 5kg spring, which I believe is still used in the new KLR, often
lets the rear end sag more than 50%, using up half or more of the available travel. A
correct spring holds the back of the bike up with 66 2/3% of total travel available. Top
Gun’s springs start at 6.6kg which is the proper spring for a 200 pounder.  How do I
know? Because with Ohlins suspension expert Stig Pettersson’s help, I experimented in
the early 90’s and finally arrived at the proper spring rates for different jobs. My all-
around spring (at 200 lbs body weight) is a 6.6kg. If I’m solo carrying lots of gear I go to a
7.4kg, and two-up with gear and Pauline, I go to 9.0kg.

The most important thing you can learn from all of this is that if the back of your KLR650
is sagging, the first thing you should do is install a heavier spring. If you install a raising
link instead of a heavier spring, you not only lock in reduced wheel travel, but you get
wallowing, bottoming and the stink bug effect when you brake hard. If you’ve made the
mistake of installing both, stay out of the dirt because you now have “less trail and more
flail”.

I adjust my rake and trail for the kind of riding environment I plan to experience. I use
three sets of links; stock, 3/4″ lowering, and 1 inch lowering. If I expect to experience lots
of sand and loose stuff with Pauline on board for instance, I would set-up her KLR as
follows:

 

  • 15/47 sprockets
  • Ohlin’s long travel remote reservoir shock with 9kg spring
  • 1 inch lowering links
  • 460 X 17 King Unicross knobby
  • Raise front of bike 15mm with fork extenders
  • 90/90 X 21 Metzeler Unicross (2mm thick tube)


If Pauline and I were going on a long two-up paved mostly mountain ride, the set-up
would be as follows:

 

  • 15/45 sprockets
  • Ohlins shorter travel street shock
  • 3/4″ lowering links
  • *100/90 X 19 front wheel and tire, 120/80X18 rear wheel and tire

* NOTE: The 19″ front wheel lowers the front end, decreasing rake and trail. If I were to
use a 90/90X21 taller front, I’d use stock links.

The main point of all this verbiage is to attempt to convince you that bike set-up has
consequences. If your expert has told you to raise your bike with links when it is
obviously sagging low in the rear, you need a new expert. You never change rake and
trail before you have the correct ride height (approximately 1/3 of total travel front and
rear with rider and gear in place). Only proper spring and pre-load can do that for you.

If your expert tells you to lower your KLR650 two inches front and rear, you’d better know
how to keep the moving parts from crashing into the stationary chassis pars.

Safety starts with proper chassis and suspension set-up and unfortunately the KLR650
comes to you handicapped by the factory. Begin with a proper rear spring.