| Author | Comment |
Jamais
Member #42
Posts: 164
(4/27/03 6:44:21 pm)
Reply | Bicycle Computer
Has anyone installed a bicycle computer.? The one's I've had on my bicycle are very accurate with addtional info such as air temperarture and time. If I add the the oil temp guage and lose the clock, the bicycle computer would be an easy substitute.
My only concern is how does one mount the magnet required for the computer's sensor? |
CYCLEROB
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Member #10
Posts: 1476
(4/27/03 10:22:11 pm)
Reply
 |  Re: Bicycle Computer
Jamais, I adapted a Sigma BC-800 to my 1150R last summer. Even now it is an absolute necessity. It was the best $27 I ever spent on my bike. Seven functions. An odometer that now shows only about 10 feet of error in a 5 mile marker highway span - - - after a few trial & error "triming" calibration number entries from the initial setting. Think about that accuracy. Ten feet error in 26,400 feet. BTW, those highway markers aren't just plunked down "over here, over there" by Billy-Bob in his old Ford Pickup. They are very accurately placed by engineering people when/after the highway is built.
About those BC-800 functions:
1) Digital clock. Very accurate. Shows only HH:MM format.
2) Average speed. Only calculates when the wheels are turning. Freezes when you stop. This one is the most fun to watch as it increments up/down while you are moving. You end up riding differently for BIG numbers on your daily trip to work.
3) Maximum speed up to 183 MPH !! Frequently shows surprisingly big numbers, like "98" when I pass 3 or 4 cars going 50 mph.
4) Main Odometer, settable to any numbers at any time, matching your bike's odometer or just zero. I will use mine for miles/year - - read/record & zero it on Jan 1st every year.
5) Trip odometer that reads to .01 mile. Great as your everyday curiosity tripmeter so the BMW tripmeter gets reset at fuel ups.
6) Trip elapsed time. Only runs when the wheels are turning. Stops when you stop. Shows you why your a$$ is sore at days end.
7) Current speed that is Dead on accurate - - in a larger size display.
It always shows the speed (big display) & one of the 5 other functions you select. There are also little icons that show under/at/over the dynamically calculated average speed. So it's really showing three functions simultaneously.
Looking at what you get from AeroStitch.com and then trying to figure out how to make it work on your M/C can seem like an impossible task. BTDT. I have to admit I overheated a few billion brain cells on my insisting on a minimalist fabrication. The upper left pic shows a wheel spins 2 mph and the tiny "down triangle" left of it means "below avg speed". The 126.77 is the trip distance. The upper middle pic's 41.18 is the average speed.
The lower left pic shows the homemade bracket without the magnet in it for clarity. There is a very thin washer between the bracket and the brake rotor's recessed washer to fill the depression so the bracket doesn't distort when tightened - - you'll see what I mean when you remove a rotor bolt. The stationary sensor is wired to a small flat piece of aluminum that is located by a 6x1mm bolt thru some thick brass collars I salvaged (unused parts) from suspension kits. It threads into the vestigal threaded lug on the lower right fork lower. It has needed nothing since the initial mounting.
"I think . . . therefore, I am" --René Descartes.
Edited by: CYCLEROB at: 4/27/03 10:40:47 pm
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Jamais
Member #42
Posts: 165
(4/28/03 9:26:05 am)
Reply | Re: Bicycle Computer
CYCLEROB, once again you've made a seemingly complex task rather simple in execution. Do you have to heat the rotor's screw to loosen it? I was under the impression that loctite is used to insure retention.
Also, is the magnet also retained in its bracket with wire? Edited by: Jamais at: 4/28/03 9:28:48 am
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CYCLEROB
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Member #10
Posts: 1477
(4/28/03 9:47:12 pm)
Reply
| Re: Bicycle Computer
Jamais, Those are good questions. No heat required. Rotor bolts are always put on with Blue Loctite, which is semi-permanent. Red Loctite is permanent & requires heat to soften it to a jell. Red can be removed without heat, but it requires lots of torque, good tools, and a fullsized fastener "head". Rotor bolts do not have a full sized head (depth of tool engagement) so your caution was wise. Removing my thread lock retained rotor bolt, wheel on the bike, seemed normal to me when I used a 3/8 drive ratchet. I remove them many times a month in my shop, using an air impact wrench, for customers having wheels powder coated. In that job, where all the bolts are removed, the wheel is laying on the floor & I use considerable body weight on the impact wrench - - then pull the trigger until the bolt pops up.
The BC-800 magnet's figure eight cross section is retained by an interference fit into the slightly narrower cut slot - - - and is held in place by centrifugal force, even after hitting multiple sharp bumps. The plastic housed magnet was meant to snap onto a bicycle spoke with a metal retainer pushed on afterward, but that method was scrapped for my install. The steel piece I used is actually a discarded sound/video card blocking plate from a computer. It was the right thickness, size & plated on both sides.
"I think . . . therefore, I am" --René Descartes.
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Jamais
Member #42
Posts: 166
(4/29/03 6:03:43 am)
Reply | Re: Bicycle Computer
CYCLEROB, many thanks. |
cheshirebiker
new user
Posts: 1
(5/1/03 4:57:21 pm)
Reply | Re: Bicycle Computer
Excellent installation ! I did mine by dismantling the magnet holder and Epoxy glueing the magnet to the wheel rim.
Your method is much neater.
I found a nice location for the computer on the left handlebar see below:
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[hr] |
Oldairhead
Unregistered User
(5/1/03 5:38:17 pm)
Reply | Key Club?
Hmmm. Some good ideas here. I've been using bicycle speedos for years on various MCs and found installation considerably eased by using "aftermarket" magnets such as the round Radio Shack magnets with a hole in the center. Just replace the stock brake rotor bolt with a longer one and fasten the magnet like an added washer. Any magnet will do, but the one furnished is both small and akward to mount.
Another tip: Sigma has a rear wheel adapter kit for bicycles that provides the longer lead usually necessary for MC installation. Or, you can just splice in some extra wire.
'Nuther tip: Don't get the wireless model. AMHIK, if you don't believe me.
Oldairhead |
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