GPS cant be trusted

Discussion in 'Cambodia - General Discussion Forum' started by dtd, Oct 6, 2009.

  1. dtd

    dtd Ol'Timer

    I was very interested in rowan's itinerary plan. he was a young and brave bloke from australia during April 2009 back then n decided to join the ride with him. he was supposed to do solo riding.

    we got in hands:

    1 GPS with up to date map installed
    a few guide books
    a few maps
    some liters of water--remember to bring lot of water with u.
    bikes with both kick start and electrict starter from mr bike rental for 15 bucks a day.

    our routes:

    pp> national road #4 > kirirom national resort ( cardamom protected area) > kamlot

    we started at around 8 am with luggages on bike after coffee and breakfast and head straight away on the routes as planned.

    while we were inside the cardamom protected area, we rode throught all terrain from muddy, sandy and rocky. at the start, everything were all good.

    however, we got lost after when we were only 30km away from kamlot. there was a route in the GPS. However, we could not find it since no more tree to cut down and the road left un-used. The grass has growned up and we lost the track. We tried doing the Z and still we could not make it.

    while getting lost, met few local people inside the jungle and asked us for MUCH money to guide us to the destination.

    around 4 PM, we were deciding if we kept finding way or heading back as the night falling down. if we kept moving on, we would make it or would not make it and had to stay in the jungle for the night, ran out of gas, or met wild animal. so we decided to come back way we did coz we were sure we could come back through the way we did.

    arrived nh4 at around 7pm and head to koh kong. while we were at koh kong, we wanted to ride into the cardamom mountain again by asking some local people for tips. we were recommended to hire a guy or a moto dob driver to guide us through. And we were told it was a real challenge.

    finally, i decided to come back pp while rowan head to sihanouk ville. rowan kept doing his trip and came back pp after getting lost at another part.


    -bring alot of water
    -kick start is a must-- i used it alot while we were inside the jungle without knowing why the battery did not work properly.
    -plan it well.
    -bikes must come with big gas tank--at least can hold up to 14 litres and keep refilling when u see big gas station on the main road.
    -should carry some gas--if u r not afraid of crash and exploding. i saw local people carrying gas in bottle. but rowan said it was dangerous. but i would do the same as the local. there is no gas station in the jungle right?
    -food in case u get lost n have to stay in the jungle.
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  3. shadow

    shadow Ol'Timer

    A GPS mearly gives you your position. This can be trusted if you have good signal strength and are not in a very urban area with tall buildings were the signal can bounce.

    It is the map that you had loaded that may have errors on it.

    Like anything know your equipment and how to use it.
  4. dtd

    dtd Ol'Timer

    rowan said it was the latest map found and installed. it would cost pretty much if it was legally installed.

    most of the info on routes are ok. yet, some small routes has disappeared or never been used for long so the grass just grown up after no more tree to cut down.

    wat is more, more small routes have appeared and the map has not yet added them in.

    on the spot, we were trying to figure out where the route was and found out self outta the track. we did like circle or Z n jumped out of joy when we were shown closed to the track. unfortunately, we could not get on the track even we were closed to.
  5. bard

    bard Ol'Timer

    Never used GPS maps in Cambodia, but I use the ESRI maps in Thailand and I never ever had a single problem with it.

    If the maps are no good, you're screwed. To plan ahead, use google earth to plot, make routes into the GPS or the best data available.

    The ride over Cardamom is already on GT-Rider, just download the track they used and voila you have the same route.

    A GPS is not a magic tool which knows it all, in Thailand a lot of roads and trails are not mapped so you cannot use a GPS solely for navigation, you can track back if you loose track. Forward planning is essential on the trails...
  6. dtd

    dtd Ol'Timer

    i solely relied on rowan to plan and arranged the stuff and emailed me ahead. i am not much into IT or good at maping though. i had to stick my arse closed to him since he was with the GSP n maps.

    still, i admired for his braveness and mapping even the failure occurred.

    he did his riding report in thailand and gave up his report on his riding in cambodia due to the failure. we lost contact since then.

    here is the link of his report but missed the report on riding in cambodia

    i want to do the cardamom this jan---cant wait-- with a mate of mine and i hope i can afford or success in doing that.

    any tip on which map to use and where to download-if possible- would be very appreciated.
  7. Marco

    Marco Ol'Timer

    This is going to be intresting as i use GPS for my work at sea and in my leasure time in Bike, never got lost or if i had, there is always alternative solution to find your self back,,, NOW saying that, i know from other posters that i.e. China Gps tracks are off by 100Meters, and that ca be very diffucult to navigate.

    but you said you could not dind the track? you did have Rowans road installed in your GPS and it gave you, What ever color you have in your GPS for assign route, what you where suppose to ride? you did try to follow that route? Did you zoom your screen to see if there is any alternative rouad's to your "Next" destination? what you could take, now bearing in mind i have never been cambodia but read far too many report that i know it's hars land to ride especially Offroad.

    Just a few question what came to my mind this early time in the morning...
  8. bard

    bard Ol'Timer

    We will ride Cardamom the 23rd of November, would be cool if more could join.

    If you look at ... t5225.html

    There is GPS track you can download and use in your GPS, also the latest Garmin maps I found for Cambodia is Version 2, which is way bigger than the Version 1. The thread poster has also been so nice as to put in the KML file of the trip, just download and use in Google Earth software.

    After our trip I will send the GPS track to Dave U, and post it here as well. We will be at least 2 with GPS maybe more, so hopefully when we send all of the GPS data to Dave U there is a chance the data is usable enough to make one track/route/map maybe. I will try to waypoint every place with fuel/guesthouse/shop/river crossing and link to picture from the tour.

    Don't want to promise too much but this is what we aim to do, hope that can help future riders.

    January, if you can't join in end of November, I might be up for a second run in January. Let me know.

    Cheers Bard
  9. dtd

    dtd Ol'Timer

    wat made me interested in joining the trip with rowan was the straight line in his itinerary. he did plan well with few guide books and few maps in hand. morever, he also brought a small notebook with google map inside drawn.

    he email me and showed me the routes. once we arrived the spot, the garmin GPS showned that we needed to move head in straight line. yet, we found no route to go. we do the ) or (. yet, we ended up doing the circle after doing the ) or ( instead and thought we could be able to get back. but WE COULD NOT.

    there was only 30km away and we would make it.

    we hit koh kong and decided to stay there for a day asking local people if we could try to hit cardamon mountain throught koh kong. we were warned not to do it except hiring local guide.

    i decided to come back pp and rowan went to shv. on the way back, we visited a water fall somewhere near sreh ambil. through the guide books, we should had parked the bike at lower part of the mountain but rowan kept pushing upwards and did the HURRAY!!!! we made it better than the book said. we parked the bikes and walked up. while walking up to the see the water fall, we were warned by a soldier who were taking a nap with his honda cub scooter not to walk up since there was a chinese factory working on something.

    well, rowan went to far and did not really listen to the guide book. by keeping pushing the bikes upwards, we got struck on a part of the mountain and asked local people to help turnign the bike around when we went back to the main raod. i falled many times and i did not wear any riding gear. ROWAN was kinda insane just like he did the straight line itinerary-- i still remembered that time. well I MISS IT.
  10. dtd

    dtd Ol'Timer

    thanks bard, i will contact u if u want to do the second run during jan or if can afford---since i am still deciding.

  11. Auke

    Auke Ol'Timer

    Don't know who is making the Version 1 and Version 2 GPS maps but here is a quick and dirty overview of several versions of GPS maps for Cambodia.

    The Rotweiler Cambodia map (not free) which is part of his Indochina map as well as the Cambodia map which can be downloaded for free from Mapcenter are both based on the Gecko map. They are very similar and while quite a few of the tracks in the maps are based on actual GPS tracks there are also a lot which have been traced from the paper map. The latter may well show roads considerable off from where they actually are while some of the roads may no longer exist.

    There is a GPS map from Asia GPS ( - need to pay for downloading) which is based on GPS tracks but is far from complete

    In addition there is the Garmin City Navigator Version 3 GPS map sold and produced by Aruna in PP which seems to be good but is not cheap (150 USD or so).
  12. MuddyMick

    MuddyMick Ol'Timer

    I have mentioned this in another topic, I will expand here a bit more, the above comments are correct, the Garmin can be off, trails and roads, especially the logging roads, can be quickly overgrown and hard to find once they stop using them. Not only is it imprortant to know your Garmin, but it can let you down if it cant "see"the sky, too much cover overhead by trees, and you cant track up. Keep an eye on time ,speed and distance travelled, ALWAYS confirm your GPS bearing with the GPS MK1, a compass! Know your maps and how to use them, more than one map may come in handy. The Cambodian Mine Action Group have some pretty damn good maps if you ask them, not to mention up to date info on any mine clearance activity in your planned riding area.

    Having 24/7 telephone support will help if you are in a coverage area, a map in Khmere and English is a bonus, providing the local can read the name of where you are heading.

    Smile, be patient, draw in the sand, stay calm.

    Water is a must, suggest buying one of those filters for trekkers at a Camping goods shop, sodium permanganate in small amouts will make water safe, but it tastes like sh*t, mixed into a dark pink paste and then thinned out with a bit of water and you have a decent disinfectant for scratches and cuts.

    Carrying an extra 2.5 litre coke bottle of petrol is sound advice, keep it on the other side of your rack, away from your pipe, and dump the petrol in as soon as you have burnt off 2.5 litres (about 60km), dont toss the bottle, keep it with you as you can refill it later, leave the cap off for a bit after you fill to let any vapours evaporate, petrol is hard to come by in remote areas. Wrapping the bottle in good old gaffer tape is added protection against heat from the sun as it is silver, and reflects. A 2.5 litre coke bottle can handle up to 6 bar of pressure before it will burst!

    Some of the lads that have done the Cardamoms will tell you the same about the value of carrying extra petrol.

    Try to carry at least 4 to 5 litres of water with you, or save weight by buying a Trekkers water filter as mentioned earlier.

    Also, a roll or two of gaffer tape can save the day! 1001 uses, god bless 3M!
  13. bard

    bard Ol'Timer

    Hmmm I was considering to put on my enduro tank for the trip, and it now seems like a good idea. The stock tank on the XR is only 12 liters, so the 21 liter Enduro tank might be what I need then...

    Good idea with the water filter, will sort that out.

  14. dtd

    dtd Ol'Timer

    if you cant change the gas tank on ur bike, bringing along with some extra gas is the ideal. Your xr gas tank can hold upto only 9.5 or about 10 litres. The gas tank for honda xr baja or suzuki djebel can hold up to 14.5 litres to 15 litres.

    the time i did and failed, we were in the first, second or third gear all the time and that consume more gas since the engine roars all the time.

    try to bring only necessary things only so the bikes wont be too heavy. the bikes must be light so it is easy to control. you will ride over the rocky parts, go throught the water-- i assumpe it is impossible to go through those water during the rainy season. i did during the dry season and, luckily, we could go thru them. Rowan got stuck once in the water and almost got his bike drown.

    keep looking at the time and gas-in case u get lost- so u can move back or decide to keep going.

    i guess even u have done it before, u might still get lost in the second or third time since the routes u have done might disappeared or more roads has come up. it should be good if you are willing to pay the local if you meet them during the time u get lost so they can sit on the back of ur bike and tell u where to go---i bet they will try to ripe u off. while we were only 30 km away from the target, we met local people but we were not willing to pay since he was asking for like 100 bucks.

    plan it well and still a plan is a plan. deal with the reality u face and think of solution right away.

    oh and tools as well.
  15. bard

    bard Ol'Timer

    You are 100% correct even the best plan can fail, all we can do is to do our best upfront to try to make it happen without failure. If reality prevents this all we can do is to deal with it and have resources to deal with it.

    Nothing is ever 100% certain, but we hope our upcoming trip will be a success.

    Yes you're right the stock tank is only 10 liter or something, which is why I got the 20 liter tank. The range on that should be sufficient whatever happens. Just keep on topping it up wherever I find fuel, the 20 liter give a lot of range but I will do some test runs in heavy terrain in Thailand to see how much the consumption is in WCS to make sure first.

    The others will carry extra fuel with them in separate tanks/bottles and should one be very low we hope the combined amount of fuel in the bikes, and tanks will be able to get everyone safely to destination.

    Cross my fingers that we are able to report a successful trip with pictures and usable data after.

  16. dtd

    dtd Ol'Timer

    bard, i feel the nice report with up-to-date info/data are coming. promise to give me the link and as many photos as possible and dig to the very dept as u can ok? good luck, mate.
  17. MuddyMick

    MuddyMick Ol'Timer

    REDEX!!!! The majic juice, if you need to buy pertrol from a roadside seller, nevermind the mix ratio, dump the entire wee bottle in the tank. Ispropyl alcohol, hallf litre bottle = Gasohol!!! in case you get some really bad petrol, this will help!

    Section of hosepipe, to borrow petrol from group members in urgent cases.

    Octane booster is also nice to have on board, buy two or three tins, you can divide it into small water bottles to share the weight amongst the group. Again, wrap them in gaffer tape for added protection, you can always reuse the tape if you need it elsewhere.

    A few cheap toothbrushes to clean chains on safety days.

    A bottle of oil, can get here, but low quality unless you can find a local shop that stocks the good stuff, no shops in the bush.

    Pipe plugs, to stop water from getting in if floating bikes over rivers, plastic, gaffer tape and cable ties are also handy, get the black uv resistant ones, they are stronger.

    Also available are cable ties with a steel band running thru them, super strong.

    Maul grips- read a few lines somewhere that a fella had broken his shift lever clean off on a fall, the Maul grips served as a shifter till he could get to a town and buy another. Clever.

    Lightweight plastic hammer wont hurt either, unless you clout a fellow tour member with it......

    Plug spanner/socket, spare spark plug

    One of those light folding army shovels might come in handy too.

    A machete, buy here, often need to cut wood, bamboo, trim killer branches fron trails for fellow riders, remember to cut them well back, dont leave a point on it, cut it straight. Know a rider that impaled himself on a cut branch, right thru the bit of meat above his collar bone. If he had got it in the throat.......dead man, close one hey?

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