Problem:

First, I have never had or used a wireless computer; all if mine are wired so I don't know that much about them except that they pick up a lot of interference and stop working. My wife recently switched from a Sun EZ-3 to a tadpole bent. She purchased a wireless Bontrager computer for her trike (before I was able to get one for her) and after I installed it, the computer didn't register any speed or distance. The initial installation of the computer was on a tee-bar mounted on the boom with the sensor on the left chain stay, fairly close to the back of the seat. I couldn't mount the sensor on the front wheel because of the disc brakes (no place to mount it). Both batteries checked out good on my battery tester.

I took the bent out for a ride down the street and held the computer in my left hand while riding and everything was working fine, until I put the computer back in it's mount and everything stopped working again. Figuring the issue here was the distance between the computer and the sensor, I mounted the computer on her left hand mirror. The computer started to register the speed and distance but the problem now is that it works intermittently.

Questions:

I'm sure someone in this forum that rides a bent has come across this problem before, so what did you do to fix the problem? Could the problem be that the signal from the sensor to the computer has to pass through the body? She is only 125 lbs.

Another question, does anyone that is riding a tadpole bent with her setup have artificial hips (the reason she is on a bent)? She has bilateral implants and I am wondering if the titanium in the hips can cause interference with the wireless signal?

Is anyone using a Bontrager Trip 5W on their bent and are you having or have had issues with this computer? I talked to a bike mechanic that worked at a Trek shop and he said that the Bontrager wireless computers are hit and miss as far as them working. Personally, I have purchased several Bontrager items and I have not had any luck or satisfaction with any of them, but that is just me.

Any help would be greatly appreciated since the bike shop she purchased the computer at is close to the only place in this area that has tadpole bents in stock and they are about 40 miles away. I really don't want to keep going back and forth to that shop to get this problem resolved.

I know that this is a lengthly post, but any help or answers would be appreciated.

Why not just go and use a wired computer. I have wired computers on both my trikes though I did have to extend the wire by splicing in a two foot section for my Wizwheelz 3.4 where the computer is on the handlebars and the sensor is at the rear wheel. It happens to be a Nashbar cheapie computer and works just fine with the additional wire spliced in. It took a little cobbling to get it in place but it worked well for the several thousand miles I rode that trike. If you need pictures of how I mounted the sensor, PM me with an email address and I will send you a picture. It certainly is possible to have the computer and the sensor on the front of a tadpole trike with disk brakes. My GS GTO is set up that way with the sensor mounted on the steering arm using a small adapter provided by Greenspeed. There are some pictures of it on www.bentrideronline.com where someone recently asked about using the Greenspeed adapter for their trike but didn't know how to attach it.

I just took a look at what is available on ebay. There are a lot of international sellers from the far east selling basic computers for less than $5 including shipping. The downside is that delivery takes about 3 weeks. That's so cheap that you could afford to experiment with one. I have ordered parts from Europe before when I couldn't find them in the US or didn't know of a US source.

Her trike doesn't have handlebars, it's a direct drive tadpole trike that steers with control arms. She had a Sigma BC-509 wired computer on her EZ-3 (this one has handlebars over the front wheel), which she still has. Sigma makes a recumbent harness for around $10.00 for that model. This is what I wanted to put on the bike in the first place, but she bought the wireless when she bought her cycling shoes. Since the bike shop she bought it at is so far away, I didn't want to have to drive 40 miles to return it, so I decided to mount it and ran into the issues above.

On one of my other forums BicycleTutor.Com one of the bent riders posted a photo on how he mounted his wireless on the caliper mount for the disk brakes by using a metal bar. I looked at my wife's disk brakes and they are a different make/model than his and they have no way that I can see to mount the sensor where the rotor isn't in the way. I'll check out that adaptor from Greenspeed and see if it looks like it will work.

I have wireless digital VDO computers on three bents. Digital signal works much better at long distances common with 'bents.
https://www.nashbar.com/bikes/Product...0_10000_202553

My experience with wireless computers is they are pretty much line-of-sight. Anything between the sensor and the head will affect the signal.

Is it possible to mount the pick up on a front wheel? I installed the pick up on my wife's Greenspeed tadpole on a steering arm so that it turns with the front wheel.

Janmm's got it. The computer you're using is just inadequate for the job. It's too far to shoot a standard signal through the rider's body. The digital ones should do better. Or get a wired computer for the rear wheel pickup.

I have both a left knee replacement, and a right hip replacement. I have a 'Cateye' 'puter on my Rover. In the paperwork it talked about a set distance that must not be exceeded. On my Rover TT was kind enough to add a sensor mount by the right front wheel, and the 'puter itself is mounted on a ACC mount right above the pedals.

With the above setup, I have not had any issues at all in some 150+ miles.

I hope this helps?

Thanks guys for all the responses. I really wish she hadn't purchased the wireless computer. She had a wired Sigma BC509 on her Sun EZ-3 bent but it had handlebars over a 16" front wheel and it worked great. Sigma has a recumbent harness for that computer for around $10.00 that I was going to order for her from my LBS, but she had already purchased the wireless. This weekend I will go over the bike again and see if I can come up with some way to mount the sensor on the front wheel rather than the back one. I had a feeling that the signal was being blocked by the body and the seat, but never having a wireless on a bent, I wanted to be sure that others have had some of the same issues I am having.

As I said, I have not had any luck with anything from Bontrager and this is no different. The instructions for this computer really suck. It is a single piece of paper printed on both sides and the foreign language parts take up 80% of the instructions. No where does it say anything about maximum distance or body interference or pretty much anything. If I were a first time computer user, I wouldn't even know about having to set the wheel size because it isn't mentioned nor do the instructions really tell you how to do the initiial settings. I had to play with it for about an hour to figure it out.

Is there a spot that you could put a Minoura mount on the control arms that would get her computer within range of the wheel sensor? My Cateye Micro Wireless has to be within 27 inches to receive the signal.
https://www.minourausa.com/english/ac...-e/lh50-e.html

I actually saw those on their web site after posting this the first time. I've bought several of their products and like them so I may see if this will work and have my LBS order it for me.

First of all, thanks for all the good suggestions. Good news is that the problem is solved. I don't know why I didn't think of this before because I was looking right at the solution all the time. It dawned on me when I was building a PVC bike lift for her bike that will raise the boom so I can close the tailgate on the truck. I took a piece of 1/2" PVC about 5" long and drilled a hole in one end and ran a #10 screw through the mounting bracket for her fenders and then mounted the sensor on the PVC. Works perfect. Just have to wait until she isn't going to ride for a day or two and paint it black. The white really sticks out. I'll post a photo tomorrow after our ride as it may help someone else in the same situation.

Update:

These photos show the method I used to mount the wireless sensor on the fender bracket. I have to paint the PVC and get a shorter screw, but it will give her a working computer until then. Sorry about the first shot being a bit blurry. It was taken with a cheap $40.00 camera that I bought to take photos of my rides. If it breaks or get lost, I'm not out a bunch of money.

About 5 years ago I started using my Garmin Legend Cx for my bike computer. It was the best thing I have ever done! There is no setup for any bike (except for adding a handlebar bracket), I can move it from bike to bike and keep an ongoing odometer, and best of all I can save my bike rides on my computer with good/bad points! The initial investment is about $200 for the GPS and software, and about $10 each for the handlebar brackets. But the benefits are well worth it!

We were talking to another rider on a similar trike as hers this past Sunday. He has a Garmin Forerunner 205 and she is already hinting for one as a Christmas present. I was looking at the Forerunner 405CX model and thinking of getting her that one. The 405CX is a wrist watch type with a heart rate monitor and much smaller than the 205. I can get the 405CX from Amazon for $253.75 with the optional cadence sensor. I guess the wireless can go on my hybrid and use the one on the hybrid for a spare. I have a wired Cateye Strada Cadence on my road bike because I also use the road bike on the trainer.