How to use a 60mm exhaust clamp to attach the Bobike Mini Standard Bracket to the handlebars of a Mountain Bike, for when the Bobike Mini child seat is attached to the bike frame using the ATB Bracket
Step 1: Gather Materials
You will need:
a Bobike Mini Windscreen & mounting arm, from a bike shop or buy online GBP 18.46 + p&p
a Bobike Mini Standard Bracket, from a bike shop or buy online GBP 10.88 + p&p
a 60mm (=2 & 3/8") exhaust bracket, from a motor factors (UK Yellow Pages: Car Accessories & Parts), or buy online GBP 1.50 + p&p
2 x M8 washers (for 8mm bolts), stainless steel or galvanised, from a hardware store or buy online GBP 0.12 + p&p
a 13mm spanner
an 8mm spanner
Step 2: Assemble the Parts (1)
If you don't want your bike to be scratched by the exhaust bracket, wrap woven cloth handlebar tape around the handlebar support arm (not shown).
Hold the exhaust clamp to the handlebar support bar, with the two threaded prongs facing down.
Step 3: Assemble the Parts (2)
With the open section of the Bobike Mini Standard Bracket facing forward, put the rear two holes of the bracket onto the two prongs of the exhaust clamp.
Put two M8 sized washers over the prongs and loosely screw the exhaust clamp nuts into place
Step 4: Assemble the Parts (3)
Push the exhaust clamp is as far forward as it will go and tighten the nuts with a 13mm spanner
Step 5: Assemble the Parts (4)
Plug the windscreen mounting arm into the front two holes of the Bobike Mini Standard Bracket
Step 6: Assemble the Parts (5)
Add the windscreen, using an 8mm spanner (the windscreen shown has lost its cloth apron, which would reach down to the brake levers)
Step 7: Review the Geometry
Stand back and look at the step-up.
The bike used for these photos is not an adult bike, which is why the handlebars and seat are fully extended. Its actaully an abandonded bike (one of many), chosen at random. I've used bricks to put the Bobike Mini seat at the height it would be at on an adult bike with the ATB adaptor
On the bike shown, the windscreen is higher than it would be on a road bike. because the handlebar support bar is at a 40 degree slope. Less slope would put the windscreen lower.
Step 8: Room for Improvement
The 60mm exhaust clamp was tried on three bikes and only just fit - with thread peeping through the Bobike bracket for the nuts to attach to. The exhaust clamp stands 90mm tall - the brand mark is three concetric circles. A taller clamp would be better.
The photo shows how the exhaust clamp follows the line of the handlebar support bar. On the bike show it is at 40 degrees to horizontal, making thw windscreen higher than normal, but not closer, as the 4 hole bracket is further forward.
The long mounting arm might work better with this set-up.
It might be possible to put a wooden chock (e.g. 1" x 1" x 2") between the handlebars and the Bobike Mini Standard Bracket, using the U-shaped part of the exhaust clamp without the C-shaped part, to make the bracket more level.