Post by bultaco on Apr 22, 2007 23:56:33 GMT -8
The following is how I made the risers for my 82 XV 750 Rice Chopper.
I used a pair of 1-1/8" diameter x 4" long lengths of Atlas shafting, you can also use chromed hydraulic shaft. make sure you have both ends of these pieces faced and centered at the machine shop, this makes for accurate drilling/tapping and the handlebar mounts will sit flush when you tighten them down, You may be able to use your original handlebar mounts, you would need a metric tap, but overall this may be an easier way to go, I chose to mount my risers solid to the trippleclamps and also wanted more thread contact than the stock mounts provided, after searching through piles of old bike frames at our local bike wreckers I found what I was looking for, a metric handlebar mount with a 12mm shaft with enough length to provide 1" to 1-1/2" of thread, I cut threads onto the 12mm shafts using a 1/2 x 20 NF die, to keep your mounts looking good while tapping the threads onto them, bolt them onto an old pair of bars and mount those in the vice.
To drill the risers I used my drillpress with a cross slide vice, Atlas shafting comes packaged in a thick protective cardboard tube, use it to cover the riser while it's mounted in the vice, drill a 29/64 hole in one end of the riser and a 5/16 in the other, open up the 5/16 slightly with a larger 21/64 bit just to let the tap bite in.
If you have trouble getting the tap started you can also use the drillpress to assist, with the riser mounted perfectly straight in the vice and centered below the drillchuck, (unplug the drillpress) mount the appropriate tap into the drillchuck, (1/2 x 20 NF for the 29/64 hole)(3/8 x 16NC for the 5/16) feed the tap into the riser and hold pressure on it while turning the chuck with a pair of pipe pliers or visegrips, use lots of oil and you'll end up with straight clean threads.
After tapping the 29/64 hole you may have to open it up slightly with a 31/64 bit to allow the handlebar mount to seat fully.
To mount the risers to the trippleclamps I used 3" long x 3/8 grade 8 bolts, 16 tpi NC. or use stainless allans, I chose to bypass the spongy rubber mounts by using large thick washers between the riser and the trippleclamp and again between the trippleclamp and the bolts, the bars feel way better mounted solid.
You'll need:
Two 4" lengths of 1-1/8" Atlas shafting.
Two metric handlebar mounts w 12mm shafts.
Two 3" x 3/8 grade 8 bolts. or stainless allans.
Appropriate washers if you choose solid mounting.
1/2 x 20 NF die.
1/2 x 20 NF tap.
3/8 x 16 NC tap.
29/64 drillbit.
5/16 drillbit.
21/64 drillbit.
31/64 drillbit.
I used a pair of 1-1/8" diameter x 4" long lengths of Atlas shafting, you can also use chromed hydraulic shaft. make sure you have both ends of these pieces faced and centered at the machine shop, this makes for accurate drilling/tapping and the handlebar mounts will sit flush when you tighten them down, You may be able to use your original handlebar mounts, you would need a metric tap, but overall this may be an easier way to go, I chose to mount my risers solid to the trippleclamps and also wanted more thread contact than the stock mounts provided, after searching through piles of old bike frames at our local bike wreckers I found what I was looking for, a metric handlebar mount with a 12mm shaft with enough length to provide 1" to 1-1/2" of thread, I cut threads onto the 12mm shafts using a 1/2 x 20 NF die, to keep your mounts looking good while tapping the threads onto them, bolt them onto an old pair of bars and mount those in the vice.
To drill the risers I used my drillpress with a cross slide vice, Atlas shafting comes packaged in a thick protective cardboard tube, use it to cover the riser while it's mounted in the vice, drill a 29/64 hole in one end of the riser and a 5/16 in the other, open up the 5/16 slightly with a larger 21/64 bit just to let the tap bite in.
If you have trouble getting the tap started you can also use the drillpress to assist, with the riser mounted perfectly straight in the vice and centered below the drillchuck, (unplug the drillpress) mount the appropriate tap into the drillchuck, (1/2 x 20 NF for the 29/64 hole)(3/8 x 16NC for the 5/16) feed the tap into the riser and hold pressure on it while turning the chuck with a pair of pipe pliers or visegrips, use lots of oil and you'll end up with straight clean threads.
After tapping the 29/64 hole you may have to open it up slightly with a 31/64 bit to allow the handlebar mount to seat fully.
To mount the risers to the trippleclamps I used 3" long x 3/8 grade 8 bolts, 16 tpi NC. or use stainless allans, I chose to bypass the spongy rubber mounts by using large thick washers between the riser and the trippleclamp and again between the trippleclamp and the bolts, the bars feel way better mounted solid.
You'll need:
Two 4" lengths of 1-1/8" Atlas shafting.
Two metric handlebar mounts w 12mm shafts.
Two 3" x 3/8 grade 8 bolts. or stainless allans.
Appropriate washers if you choose solid mounting.
1/2 x 20 NF die.
1/2 x 20 NF tap.
3/8 x 16 NC tap.
29/64 drillbit.
5/16 drillbit.
21/64 drillbit.
31/64 drillbit.