Compass for bike
 

I'm after a small basic compass to fit on the screen of my bike, any one know where to get something in the UK? Or do you think the bike electrics will effect it too much?

I believe that you are supposed to use a compass well away from any large metal objects, such as cars or bikes, as it affects the bearings. Having said that, my mate's got one in his fiat panda!



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Sean

I've had no luck getting a compass to work on my KLR: Too much metal. I do have one attached to the cross bar. It detaches easily and I use it away from the bike for an acurate reading.

Ah that also answers another question thanks - nowI know why people have £200 GPS systems rather than £2 compasses!

I've seen (magnetic) compasses being used in planes, which to my knowledge fall in the category "large metal objects".

The deviation incurred by the metal is corrected using small screws / magnets, equal to the deviation correction on a more expensive compass. So i haven't looked for car-compasses which can be corrected, but they should be around. However expect to pay more than 2 quid for one, as a decent handheld compass costs around 20 pounds.

Hope this helps.

On ships the correction of the compass for (magnetisable) materials in the vicinity indeed works with small magnets, mostly done by specialised people. This helps to take away the largest deviation. Then, what is left (usually in the order of max 5 degrees) you'll have to read from a table that is provided by the specialised person, the correction depending on the course you are going at that moment.

The problem on motorised vehicles is the fact that the magnetic field lines around it are far from constant. Switching on your headlight will already have an influence, also because of the low voltage (12 V) and therefore stronger currents all producing stronger magnetic fields. Things like alternators also tend to produce strong magnetic fields.

So, a compass mounted on the handlebar would never be really reliable. I would advise the suggestion in the other reply, have it at hand, but before taking your bearing walk away from the bike (also when the engine is not running!).

Auke

Ok I will see what I can obtain locally and try different positions on the bike with engine running/not running and let the 'board know. Thanks for all for your advice

Buy a cheap "scouts compass" and put it in the map case on your tank bag. Worked fine for me. This mount also reduced vibration in the compass, but you have to find a position where the compass would be fairly horizontal. Great alternative to GPS. http://www.horizonsunlimited.com/ubb/smile.gif

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Dag
http://RocinantesTravels.com

Great idea will try it when I can find a suitable shop

Hai,

Also a "cheap" solution is an electronic compass. They are made especially for car's. I think VDO-dayton has one, and most car-accecoiry-shops will have it.
But..... for a few $ more you have a cheap GPS-receiver, wich is far more acurate and has much more possibility's.

Maarten

Tried a cheap compass on top of my tank bag but no use - next step GPS it seems.

I got a GPS (Garmin Etrek) in Canada for 200 dollars ... which works out at about 80-90 £STG at the moment ... bargain!

There is a handlebar mount available as well.

Check out the Mountain Equipment Co-Op (I think they are online).

Cheers, LJFC.

Cheers for that:
http://www.mec.ca/Products/product_d...3Eprd_id=17629

Seems pretty neat. Let me know how you get on with it please

ta
paul

Ah .... in a high-tech world how quickly we forget the basics!

This is a good solution for any vehicle mounted compass (old army trick - good for planes, cars, armoured vehicles!):

Mount your compass wherever you decide. Then move out into an open field etc away from powerlines (don't forget to beware of underground pipes for sprinklers/gas etc) and get a mate to stand at LEAST 30m away and shoot a bearing on him. Note it down.

Next dismount your compass and walk over to your mate and shoot the back-bearing - this avoids introducing another compass with another possible compass error!

Then it's just a matter of comparing the vehicle-mounted compass bearing with the non-metal influenced back-bearing (ie subtract 180deg from back-bearing).

That will give you a quite accurate indication of the magnetic influence induced by the location of your compass on the vehicle!

Repeat as often as you change bike configuration and do it twice - engine on versus engine off!

P.S. Yes I also use a GPS, but I only switch it on AFTER I've come up with my location using map, compass and odometer - use it to check. As for vibration - I don't actually mount the compass directly on the bike - keep it in chest pocket and stop to pull it out if needed (still do the above procedure though).

I think GPS is a great and helpfull tool. But in all cases always take a good old compass with you as a backup. And also familiarise yourself with the techniques to use it!!!
A very usefull book that can help you with the basic navigation skills is:
Mountain Navigation by Peter Cliff. I think you should find it in most outdoor shops. I bought it in Scotland.
Next step: get out into the field and practice!!! Makes it a lot easier when it is for real!

In my experience best to forget mounting one one the bike.I tried it myself again recently after buying one in Germany.It was great until we started moving then it was useless due to magnetism on the bike.Best thing is to put a Sylva hiking compass it the map window on your tankbag and re check bearings when the engine is switched off.Always keep a check with GPS if poss but remember one simple rule.If you don't know where you are at any time,stop and take a bearing or GPS reading,you shouldn't be moving if you don't know you location.
I have been trying to find a method of keeping track of direction without stopping for a while but the truth is I haven't managed it yet.Good luck
Roy F

Just a reminder, GPS compasses will only give you the correct bearing when moving faster than 10 km/h. They don't actually have a compass built in then figure out your bearing from your track.

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A.B.
www.ShortWheelbase.com

I found a couple of compasses especially designed for boats, cars,... They ain't that expensive next to a quality compass. They can compansate up to a 45° deviation caused by the bike (or boat, car,...). You have to calibrate them yourself on installation.
I haven't bought one but like the idea. Any thoughts?

Where did you found them? And how much? I have a couple of bikes so a compass in a tank bag is my favoourite solution if they work!

I found them in a Belgian Outdoor shop: AS Adventure.
It has been a while since I was there and decided not to buy it because somebody explained me that only one correction is not enough. Way to complicated for me to understand all the stuff.
I decided to go with the classic compass in the pocket and a Garmin Etrex mounted on the bike. I guess that these two things in combination with some good maps and experience should do it.


If you want I can go back and write down the prices and brandnames. Just let me know.

I’ve had good luck with Auto Guide compasses. Some of the models allow to adjust both N/S and E/W directions giving you a good reading.

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A.B.
www.ShortWheelbase.com

Gone for a GPS but thanks for all your help

hi, yes aircraft are `large metal objects` but they are made of aluminium, which doesnt affect magnetic feilds at all.ships on the other hand.....

i had a SUUNTO electonic watch compass(and barometer-altimeter-and it told the time!!)and it was a great gadget! but a cheap hiking compass(the square, see through base one)was better because you can lay it on your map and read it accurately.

I have found the automobile compasses work fairly well on my bike. Buy an adjustable one specifically made for an automobile. Mount and adjust per the instructions. Now these compasses are not made for fine navigation. The graduations on mine are something like 10 or even 20 degrees. I would not want to use them to find my way through the woods at night, but they work just fine for general direction on unknown backroads.

Regards,

John

I have been in touch with silva which have there own web site and thay say there adventure compass has compensators, I am taking a multi navigator (silva) also has compass and looking to mount a compass on to the bike as well. As for garmin gps systems no good if u are going to russia

Oldbiker,

What do you mean, "GPS no good in Russia"?
Because of lack of data?

Did you already use the compass? How did you mount it on the bike? Does it really work?

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http://users.pandora.be/pieter.maes2/

H.S.Elmac Ltd in the UK supply compasses for vehicles. They are easily fitted to motorcycles and have multiple compensaters. I had one fitted to the top of the screen on my Africa Twin and once set up it worked faultlessly. I haven't bothered fitting one to my BM though as I have GPS. There web site is: www.offroadstore.co.uk

[This message has been edited by mcdarbyfeast (edited 18 February 2003).]

Big subject, the compass. I went thru several and am presently using a Suunto auto compass sold by Aerostitch. Initially I mounted it on my windshield but since I ride off road 50% of the time the vibration broke it fast. I got a new one on warranty and disassembled the base to make it
flat on the bottom and added a piece of velcro so I can stick it on my tank bag. It is a fairly large liquid capsule compass. This compass has internal magnets so you can adjust it for the magnetic interference of the bike. It works fairly well when correctly adjusted and I like it since it provides a general direction of travel and helps if you get turned around like I sometimes do in either urban or off road situations. With the velcro I can pull it off and stash the unit when not needed. You need to carry an extra compass to set it in case it gets knocked out of adjustment. Hey, it isn't perfect but at least I don't do the GPS shuffle when I stop trying to find which way north is. To be honest I use it most on the road when I get turned around and don't go 20 miles out of my way. Bill.