OF BARS AND MEN

 

OF BARS AND MEN

OF BARS AND MEN

Another Bar

Immediately bars are mentioned the mind fills with all manner of beverages, banter, foaming pints and
other things. However, a reader has asked me to write an article, as I currently have plenty of downtime,
on the subject of handlebars and general set up for Vintage bikes.

Over the years there have been many changes in style, position, shape and construction, from the
almost flat wide steel bars of the 60’s and 70’s, the transition to the hi-lift alloy Renthals, then the
addition of the cross brace and now the fat bars with a lower rise on just about all modern machines.

1963 and flat as a pancake bars on the Greeves 24 TES

So there are many factors that determine how you set your bars and levers and I’ll try and spell them
out and go for the “average setting” from which the reader can then use as a datum and adjust
accordingly to what suits him or her best. Perhaps we should look at all the other factors that also
contribute to the overall set up and final positioning of the handlebars.

Riding posture is a key so using the bike’s 4 shocks and the human body’s other 4 of elbows and
knees the perfect posture should incorporate all of these and the rider should be in a classic “banana”
bend when standing on the rests.

The classic “Banana Bend” and “8” shocks all working

Over the years the position of footrests have changed going from solid weld ons which were usually
too far forward as trials bikes were originally transformed road bikes, through the spring loaded style
which invariably got mounted too high up causing the rider to have his center of gravity too high up and
thus weight too far forward. Currently it would seem the ideal position for footrests is about 12 inches
high and on a line with the leading edge of the rear tire. Generally speaking, irrespective of the type
of fork being used, or the offset of the top yoke the distance from the center of the front spindle to
center of the footrest should be 37.5 inches. Further back and the front wheel will lift too easily and
may become difficult to hold down on long uphill climbs, too much further forward and the machine
will be difficult to control in tight turns and steep downhills as the rider’s weight will be too far forward
and over the front wheel causing plowing in turns and the classic “A over T” on downhills.

Repositioned pegs on the Cub,  2″ down and 2″ back

Taking the shape of the bars into account the best type of bars to replace old bent steel bars from the
70’s must be the Renthal 5.5 or 6.5 inch lift with crossbrace in light alloy. Personally at 5′ 10″ I prefer
the 6.5 lift for most machines with 29.5 inch fork legs. The Enfield however has 31.25 inch legs and I
have therefore gone for a lower lift set up here to compensate for the longer legs.

Standard Renthals with crossbrace

Lower lift Hebo bars to compensate for the long legs of the Enfield, and
yes they go all the way to the top!

As a general rule the “bend” of the bars should be parallel to the fork leg. Rotating the bars forward
will give quicker steering as per the current model machines, but on older bikes may well put too
much weight on the front wheel. So start parallel to the forks then try a few degrees forward anywhere
up to vertical relative to the ground.

OEM bars set at the “Datum” on my 74 SSDT replica

Unbraced wide Renthals set a few degrees forward from the “Datum” on
my “No Excuses Cub”

Moving on to levers, and lets discuss what normally goes wrong here……… over tightening!!! Levers
should be adjusted on the bars such that they can just be moved with finger pressure and this will save
countless replacements which either snap half way along or through the “perch” whenever the bike is
dropped. To get the best out of your levers set them such that they are an extension of your forearm,
thus if it were a road bike you would set them around 5-15 degrees from the horizontal. However, as
most of the time you will be standing on the pegs set them around 15-30 down from the horizontal in
a position where they naturally come to hand.

Levers become an extension of your forearm

While on the subject of levers some of my favorites are Magura for the front brake and  Works
Connection or Moose for the clutch which have needle roller bearings in the pivot point and make for
a silky smooth operation if you must use the clutch!!! Remember older Vintage Trials bikes were NOT
intended to be ridden using the clutch under ANY circumstances as traction was achieved using
throttle control and the flywheel.

Good quality front brake lever by Magura

A clever clutch lever from Works Connection with needle roller bearings

Another needle roller clutch lever by Moose

Clearly that must bring us to the Throttle and here I would use Domino which has the 90 degree pull.
They come with 2 choices of action either fast or slow, the color of the barrel indicating which is which.
Black = Slow and White = Fast and generally speaking the slow action would be the best bet for a
Novice rider or anyone using an older 4 Stroke which has an Amal carb fitted. Amal make throttles of
a similar design but I find the barrel length too small for the span of my hand.

Neat and simple throttle from Domino

If you are using OEM throttles from the 60’s and 70’s these required longer cables as the entry point
into the throttle mechanism was at 90 degrees to the bar. If you plan on using this type then about a
45-70 degree upward position was the best and a fair amount of electrician’s tape was used to give
some form of rigidity to prevent winter tree branches from catching under the cable and giving you an
unexpected burst of power. When setting up the throttle cable many of “us” older riders prefer Zero
tickover and indeed a little slack before any take up which allows the flywheel to have its full
capabilities and also allows very slow tight cornering without any use of that clutch thing!

Irrespective of what throttle that is being used always make sure the end of the rubber is not fouling
the bar and again don’t over tighten for the same reason as discussed under levers. Should you drop
the bike on the right side then always check the throttle operation before restarting and adjust
accordingly.

Decompressors, where fitted, serve multiple purposes ranging from a kill switch on older bikes, and
an excellent form of braking on bikes with very poor brakes like the Ossa. Most of the older Doherty or
Amal levers are pretty crude and have a large mounting platform which can get in the way of the clutch
but Domino produce a neat unit or Works Connection have an excellent integrated control mounted
on the clutch lever as I use on the Enfield.

Clutch and Decompressor all in one unit

Works Connection integrated unit as used on my Enfield

Finally while doing all this work on set up make sure you have “good” cable runs and those that move
are positioned in the correct sequence with the front brake cable usually forward of the others and free
to move with the compression and extension of the forks. Keep the clutch cable in the smoothest
flowing direction to avoid any tight bends, and finally turn the bars on full lock in both directions to ensure
no binding or sudden acceleration from the throttle.

A lot of cables and controls

Simple layout on the Cub

Well there are some views and tips for the “new to vintage trials” readers, try them, see how they feel
and then adjust accordingly for your own personal preference.

TONY DOWN

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Comments
  • 8/21/2009 4:36 PM Don Hale wrote:
    Tony – I stumbled on your website – very interesting. I’m new to trials and would like some tips on setting up the bars on my 1978 199 350 Sherpa T. Some of the terms you are using are unfamilar to me. I was wondering if I could call you and talk on the phone. If that’s all right send me you tele. number and the best time to call Thanks Don Hale.
    Reply to this
  • 5/23/2011 7:37 PM Mike Austin wrote:
    as a new old guy to trials I found the information very valuable, I will be following your website closely.
    Thanks: Mike Austin (1968 Greeves Wessex)
    Reply to this
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