10 Making a set of pullbacks...

A blow by blow photographic account of chopping from stock to chop... This projcet has been given its own forum due to the large number of photos it contains making uploading slow for those of you still on "dial up".
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Prof
Founder, Choppers Australia
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10 Making a set of pullbacks...

Post by Prof » Sat Nov 11, 2006 9:20 pm

Making a set of pullbacks...
Michael is pretty set on having pullbacks so first step is to cut a couple of piecs of 1" tube to length plus an extra foot. Mate has just built a bender for 1" and 1 1/4' tube, so we're going to give it its first job. Tube is 2mm wall thickness rather than the common 1.6mm... .4mm makes a lot of difference in strength...

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Here's bits of steel tube (plus spare length) and my pattern on carboard. Michael sorted out where his hands were most comfortable resting, so we made up a pattern and drew it onto cardboard. The two bends in each piece will be in same plane, because he has long arms and bars do not have to come back too far.

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We are using a piece of pre-bent tube to work out what radius the bends will be on our bars. We are using weld join on tube as our reference line and have marked out distances from a starting point on each piece of tube at 5mm spacings. this way we can start bends in correct places on first piece and then measure of to the markings on the second bar to get everything equal...
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First bend on first piece. Mark on white sticker tels us how far bender has been rotated so we can match next bend. Pointer is past pencil mark because of "spring back". New mark will now be made

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Bent bars home and cut to height with angle grinder with 2mm cutting blade. As with down tubes, I have used a pipe cutter to run a mark around bars for a more accurate cut...

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Inserts turned up on lathe, drilled and threaded and hammered into ends of tube. To prevent damage screw a bolt and spacer into insert and hammer on the bolt. These were a very tight fit. If you want to be fussy, you can put inserts into the freezer and heat tube, but then this is a Harley!

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Before hammering inserts, we drilled 3/8 holes through both sides of tube. these have now been welded... it ain't gonna move baby! Final filing will correct slight off squre cut of this tube. Other was fine.

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While Paul and I were checking out the bars for fit, Rilda decided to get in on the action. Best handlebar width is for thumbs to be about shoulder width apart. Cutting off 120mm from each bar gives us a handle bars that are 685 wide. This will be comfortable, not too wind catching and give quick response.

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Bikes getting a nice stance, with flowing lines and good visual balance... plus it wil be a comfy cruiser...

Last job is to build a speedo mount, which will double as strengthener of the bars.
New speedo has arrived so now to mount it and the bars will be ready for the chrome platers...

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Bar strengthening gusset and speedo mount is made from sheet metal. Smaller notches are for handle bar tubing and large cut out is for speedo cowl. the bulk fo the bracket that runs down the front of the bars cannot be seen here as it is in vice...

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Gusset is tack welded to bars while mounted on bike to keep everything alaigned. Alaignment is triple checked as this blokes brain does play tricks!

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Speedo cowl is welded to gusset and bars. I bent cowl in a sheet metal roller, but you can do it in a vice or clamp it around a piece of heavy tube. A mistake I made was to put the cowl's welded join at the bottom where it shows for its full length. It should have been at the top where it would not be seen...

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Fitting the side gussets to strengthen and neaten the whole job up. Note how main gusset has been trimmed and folded down slightly to meet side gusset neatly. The two small holes at the top are for oil pressure and generator charge lights which I've taken out of the original speedo/tacho housing...

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Finished welding. Has been smoothed with diegrinder and file. Bronze weld tends to end up with tiny holes that show up when chromed. They can be covered by extra coats of copper by the platers, but be aware that this makes the bar diameter slightlly larger so the controls are difficult to fit and need slight filing out.

Michael wanted a mini speedo and mini tacho which I would have mounted the same way just side by side... however it was above the budget this time around... but these bars might be for sale down the track when he gets some more cash for what he really wants...
Chopit'nrideit... Prof

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