Through a few other threads on here I've been asked questions about how I put together my bike to bike radio setup, and the equipment I used, so I figured it was easiest to put it all in one place with details of where to get the bits from and how it all works, along with prices.
I wanted a bike to bike setup as my girlfriend has just bought her first bike and I thought it would allow us to go for rides together and have me be able to give her a bit of instruction along the way. I should add that years ago I was an instructor so I've a bit of experience at that.
I also wanted to do this on a reasonably tight budget so spending £120 per radio plus ancilliaries was out of the question. I already had an autocom intercom on my bike and so we also both had headsets already fitted into our helmets. The autocom is bike powered and fitted into where the tool tray is under the pillion seat of my r1150gs. I had already taken the tool insert out and fabricated a fiberglass box for it, which you can see in this thread.
I researched posts on various pmr radios but one problem they all have is that current legal radios don't have a removeable antenna and they're limited to half a watt.
Now what I've done is technically illegal, however the pmr bands are not policed and, as long as you're sensible, you're unlikely to ever have someone pull you for it. However, this is what I've done and if you choose to do the same thing then on you're own head be it.
So, with that out of the way, here we go. I could have bought something like the puxing 777/888 radios from china, which have mixed reviews. Some love them, some find they're unreliable. I chose to buy an older Kenwood pmr radio, the TK-359. These are bulletproof, mil-spec I believe, and reliable. They have about 250 channels available for you to program and each channel can be set to 1, 2 or 4 watts transmitting power. I bought them from a seller on ebay called littlegems149. He has quite a few of these still available here. They cost £30 plus £3 shipping each.
He very kindly programmed 16 channels to be the same as the Kenwood pmr channels so that if you're riding with other people using other kenwood radios they'll be compatible. These 16 channels are set at 2w. You can program another 16 at 1w or at 4w etc if you have the software and an appropriate cable. The software I downloaded from the internet and the cable I bought on ebay here for under £4. You need a dos compatible computer to use it but I have a program on my Mac that allows me to run dos software and a usb adapter that gives me access to a serial poert. I'll get round to programming more in eventually.
One useful thing about this is that if you're going abroad and the pmr frequencies are different then, as long as they're within the range of the radio,you can program them in advance and you're legal abroad too. Handy.
I bought an autocom-Kenwood cable (part 2355) from chainspeed which was £10 which meant the radio was now plugged into the intercom. The radio would trigger off the vox via the autocom and transmit.
Now, I wanted to have the radio bike powered. There's an option to power a kenwood radio from the autocom but it only works for radios up to about half a watt, which wouldn't provide enough power for the TK-359 and I didn't want to damage the autocom. I ended up buying a couple of battery eliminators for another kenwood radio on ebay, these ones, and modifying them.
I broke the plastic casing off them and, after carefully noting which wires were positive and negative, soldered on new longer wires for input and output. The insides (sorry forgot to take a picture before I modded them) consist of a small circuit board and an aluminium heatsink plate. I carefully folded the heatsink over the circuit board as it's attached to the transistors and you're bending their legs. This made for a very small little package. I then put insulating tape round it, mixed up some 5 minute epoxy and then filled all the gaps with it, potting it into a solid block.
I then wrapped it in self-amalgamating tape, just to be on the safe side, but leaving the aluminium heatsink exposed.
If you take the battery off the TK-359 is becomes quite a small little radio, not much bigger than a packet of cigarettes. The battery connections are a couple of strong little spring clips which are held in by screws. In the photo below I've removed one of the clips, you can see the screw hole and the screw holding the other one in.
I found a couple of small ring terminals in my electrical box and soldered them onto the ends of the power wires. They needed a little bit of sanding with a dremel to fit snugly and then you just use the screws to screw them onto the terminals of the radio. I wrapped some tyre inner tube around the radio to protect it and stop the controls from moving when riding.
I have a centech fusebox that all the ancillary electrics are wired into, it has a relay so is only live when the bike powers on. Turn the bike off, and all the power to the autocom, radio, gps etc goes off.
So, I now had a bike powered bike to bike radio. However there was one last thing I wanted to do. Having a little rubber antenna lying flat under the seat wasn't going to do the radiation pattern much good, and I wanted an external antenna, as that has more impact on how well you transmit than just bumping up the power.
The antenna connection on the radio is a motorola style stud and most external antenna's come with a bnc fitting, so I needed an adapter. Once again, ebay found me a couple of these which were less than £10 shipped for the pair.
Now I just needed an external antenna. Most of the ones I'd seen are 1/4 wave and require you to mount them on something metal as a ground plane. Base loaded is better as you can mount it anywhere, and half wave gives you better transmission. Google searching found a thread over on bikers oracle where they'd been talking all about this and where someone was putting together a kit of an appropriate antenna, cables and a mount that fits behind your number plate. If you skip to page 18, comment number 178 you'll find the latest prices and the person to contact for them. £36 for the full kit of base loaded 1/2 wave antenna, number plate mounting kit, cable etc and he'll make the cable whatever size you need, it's 2m as standard.
I ordered 2 kits, one for me and one for the girlfriend and have installed them, they're great pieces of kit and very well made.
The antenna on mine is a little bent because it's just tall enough to rub against the bottom edge of the top box. I ran the cable up behind the number plate (clips are included) and it plugs into the radio under the seat. The mount is threaded so you can simply undo the antenna when you don't need it and put it away. The kit includes a screw on cover to protect the antenna socket on the mount from grime when the antenna's not in use
The whole set up under the seat looks like this: I've since added a ground loop eliminator on the audio line from the iphone/gps.
On my girlfriend's bike, I didn't bike power it as she isn't planning to keep it long term, just until she's passed her test. As she doesn't have an intercom on her bike we needed a way to interface the radio to her autocom headset. Fortunately autocom make a special unit for this. It's a little box with a PTT button on a lead, a lead for the radio and a socket for the headset. It has some noise cancelling electronics in it too which helps make it sound decent. I fitted the ptt to the left bar where she can push it with her thumb, and the rest of it and the radio go into the space under the seat. As the radio is running on battery nothing else needs power so all she has to do is turn on the radio, plug her headset into the socket I've stuck on the tank and away she goes.
Again, I got the little autocom box from Chainspeed for about £45, and they've been brilliant about answering my questions as I put all this together. Highly recommend people who always seem to have time to help.
I don't know what the range is like on this yet, as I'm riding behind her, but it's very clear at the speeds we've used so far.
For the future, I have the spare battery eliminator to wire to her next bike and we then have a system that will work for us in the future when we go on tours. If I fancy going ahead on a bit of fun twisty road I can do so without worrying that we'll be out of contact and she'll know she can get hold of me if she needs.
All in, the entire setup, not including the original autocom and headsets, has cost the following.
2 Kenwood TK-359 Radios £66
1 Autocom lead £10
2 Battery eliminators £15
1 Programming lead £4
2 Antenna Adapters £10
2 Antenna & mount kits £72
1 Autocom kit 21 radio interface £45
-------
Total £222
I also bought a mains charger for the radios from amazon for £20, which means we can charge the radio she uses and also put the batteries back on and use them if we want to else where. I'm taking them on a family ski holiday in a couple of weeks.
Hope that's of help to someone.
Cheers,
Justin.
I wanted a bike to bike setup as my girlfriend has just bought her first bike and I thought it would allow us to go for rides together and have me be able to give her a bit of instruction along the way. I should add that years ago I was an instructor so I've a bit of experience at that.
I also wanted to do this on a reasonably tight budget so spending £120 per radio plus ancilliaries was out of the question. I already had an autocom intercom on my bike and so we also both had headsets already fitted into our helmets. The autocom is bike powered and fitted into where the tool tray is under the pillion seat of my r1150gs. I had already taken the tool insert out and fabricated a fiberglass box for it, which you can see in this thread.
I researched posts on various pmr radios but one problem they all have is that current legal radios don't have a removeable antenna and they're limited to half a watt.
Now what I've done is technically illegal, however the pmr bands are not policed and, as long as you're sensible, you're unlikely to ever have someone pull you for it. However, this is what I've done and if you choose to do the same thing then on you're own head be it.
So, with that out of the way, here we go. I could have bought something like the puxing 777/888 radios from china, which have mixed reviews. Some love them, some find they're unreliable. I chose to buy an older Kenwood pmr radio, the TK-359. These are bulletproof, mil-spec I believe, and reliable. They have about 250 channels available for you to program and each channel can be set to 1, 2 or 4 watts transmitting power. I bought them from a seller on ebay called littlegems149. He has quite a few of these still available here. They cost £30 plus £3 shipping each.
He very kindly programmed 16 channels to be the same as the Kenwood pmr channels so that if you're riding with other people using other kenwood radios they'll be compatible. These 16 channels are set at 2w. You can program another 16 at 1w or at 4w etc if you have the software and an appropriate cable. The software I downloaded from the internet and the cable I bought on ebay here for under £4. You need a dos compatible computer to use it but I have a program on my Mac that allows me to run dos software and a usb adapter that gives me access to a serial poert. I'll get round to programming more in eventually.
One useful thing about this is that if you're going abroad and the pmr frequencies are different then, as long as they're within the range of the radio,you can program them in advance and you're legal abroad too. Handy.
I bought an autocom-Kenwood cable (part 2355) from chainspeed which was £10 which meant the radio was now plugged into the intercom. The radio would trigger off the vox via the autocom and transmit.
Now, I wanted to have the radio bike powered. There's an option to power a kenwood radio from the autocom but it only works for radios up to about half a watt, which wouldn't provide enough power for the TK-359 and I didn't want to damage the autocom. I ended up buying a couple of battery eliminators for another kenwood radio on ebay, these ones, and modifying them.
I broke the plastic casing off them and, after carefully noting which wires were positive and negative, soldered on new longer wires for input and output. The insides (sorry forgot to take a picture before I modded them) consist of a small circuit board and an aluminium heatsink plate. I carefully folded the heatsink over the circuit board as it's attached to the transistors and you're bending their legs. This made for a very small little package. I then put insulating tape round it, mixed up some 5 minute epoxy and then filled all the gaps with it, potting it into a solid block.
I then wrapped it in self-amalgamating tape, just to be on the safe side, but leaving the aluminium heatsink exposed.
If you take the battery off the TK-359 is becomes quite a small little radio, not much bigger than a packet of cigarettes. The battery connections are a couple of strong little spring clips which are held in by screws. In the photo below I've removed one of the clips, you can see the screw hole and the screw holding the other one in.
I found a couple of small ring terminals in my electrical box and soldered them onto the ends of the power wires. They needed a little bit of sanding with a dremel to fit snugly and then you just use the screws to screw them onto the terminals of the radio. I wrapped some tyre inner tube around the radio to protect it and stop the controls from moving when riding.
I have a centech fusebox that all the ancillary electrics are wired into, it has a relay so is only live when the bike powers on. Turn the bike off, and all the power to the autocom, radio, gps etc goes off.
So, I now had a bike powered bike to bike radio. However there was one last thing I wanted to do. Having a little rubber antenna lying flat under the seat wasn't going to do the radiation pattern much good, and I wanted an external antenna, as that has more impact on how well you transmit than just bumping up the power.
The antenna connection on the radio is a motorola style stud and most external antenna's come with a bnc fitting, so I needed an adapter. Once again, ebay found me a couple of these which were less than £10 shipped for the pair.
Now I just needed an external antenna. Most of the ones I'd seen are 1/4 wave and require you to mount them on something metal as a ground plane. Base loaded is better as you can mount it anywhere, and half wave gives you better transmission. Google searching found a thread over on bikers oracle where they'd been talking all about this and where someone was putting together a kit of an appropriate antenna, cables and a mount that fits behind your number plate. If you skip to page 18, comment number 178 you'll find the latest prices and the person to contact for them. £36 for the full kit of base loaded 1/2 wave antenna, number plate mounting kit, cable etc and he'll make the cable whatever size you need, it's 2m as standard.
I ordered 2 kits, one for me and one for the girlfriend and have installed them, they're great pieces of kit and very well made.
The antenna on mine is a little bent because it's just tall enough to rub against the bottom edge of the top box. I ran the cable up behind the number plate (clips are included) and it plugs into the radio under the seat. The mount is threaded so you can simply undo the antenna when you don't need it and put it away. The kit includes a screw on cover to protect the antenna socket on the mount from grime when the antenna's not in use
The whole set up under the seat looks like this: I've since added a ground loop eliminator on the audio line from the iphone/gps.
On my girlfriend's bike, I didn't bike power it as she isn't planning to keep it long term, just until she's passed her test. As she doesn't have an intercom on her bike we needed a way to interface the radio to her autocom headset. Fortunately autocom make a special unit for this. It's a little box with a PTT button on a lead, a lead for the radio and a socket for the headset. It has some noise cancelling electronics in it too which helps make it sound decent. I fitted the ptt to the left bar where she can push it with her thumb, and the rest of it and the radio go into the space under the seat. As the radio is running on battery nothing else needs power so all she has to do is turn on the radio, plug her headset into the socket I've stuck on the tank and away she goes.
Again, I got the little autocom box from Chainspeed for about £45, and they've been brilliant about answering my questions as I put all this together. Highly recommend people who always seem to have time to help.
I don't know what the range is like on this yet, as I'm riding behind her, but it's very clear at the speeds we've used so far.
For the future, I have the spare battery eliminator to wire to her next bike and we then have a system that will work for us in the future when we go on tours. If I fancy going ahead on a bit of fun twisty road I can do so without worrying that we'll be out of contact and she'll know she can get hold of me if she needs.
All in, the entire setup, not including the original autocom and headsets, has cost the following.
2 Kenwood TK-359 Radios £66
1 Autocom lead £10
2 Battery eliminators £15
1 Programming lead £4
2 Antenna Adapters £10
2 Antenna & mount kits £72
1 Autocom kit 21 radio interface £45
-------
Total £222
I also bought a mains charger for the radios from amazon for £20, which means we can charge the radio she uses and also put the batteries back on and use them if we want to else where. I'm taking them on a family ski holiday in a couple of weeks.
Hope that's of help to someone.
Cheers,
Justin.
Ken.
