173 replies to this topic

[nofreeride]

Tri-Magnum Reverse Gear

Thread from ADVRIDER

A couple things I found. This first guy looks like he did something similar to what you tried, Nitro, but maybe he didn't really have enough torque either.

[Nitrotate]

I've seen that first one and that was one of the ideas I was going to try, using that metal drum and just welding some beads across it but after seeing how much pressure I need to put down on the tire with the gear teeth I can tell already that idea would only slip... especially if wet.

I like some of those ideas on the second link you have there though, haven't seen that before...hmmmm

[Nitrotate]

Ok so here is the video over on my thread...

http://www.fjrforum....54

[nofreeride]

Some progress...

 

 

The bike is mounted in four places as shown, on the front fork tube tabs, left and right engine mount bolts, and the rear frame.

 

 

Next up is the seat brackets, hood/windshield frame and cowl.

[k7lvo]

This one's been around for quite a few years and many thousands of miles. It doesn't have reverse. Not the most ideal solution, but it's worked for him.

Take a look at this one - it's BMW-based, but it shouldn't be too hard to slip another brand/model in:



Clicky

[Nitrotate]

Just an observation and tip that I've been thinking about... I don't know exactly how reliant the headers are on air cooling but in both of our configurations the headers get pretty much zero airflow so just to be safe I'm mounting an extra cooling fan pointed at the headers. Not sure if it's a waste or not but I'd rather have SOME airflow over them as opposed to none. As a matter of fact I should have a cooling setup that is way more efficient than the bike originally came with since I have 2 radiators and 2 radiator cooling fans and then a 3rd fan aimed at the headers. Just something to think about.

[ionbeam]

Is there a way to install a chin spoiler down low, like they do on the front of cars to get air to flow?

[Nitrotate]

I thought about that but it would have taken up too much room underneath and I'm already worried about bottoming out if I come to a speedbump...

[nofreeride]

Is there a way to install a chin spoiler down low, like they do on the front of cars to get air to flow?

The T-Rex does have a lip protruding below the radiator to direct cooling air from underneath the car. I was planning on running the FJR radiator with the original puller fan in the stock location, with some way of coaxing the air to the front of the radiator. If necessary, I will add an auxiliary pusher fan with a manual switch (for idling in hot weather).

The headers are cooled by the air coming off of the radiator, and by any airflow from below the bike. I don't see how it would be a lot different in my application.

[Nitrotate]

Ok, yeah if you are routing air around with a scoop and the fan/radiator are in the same place then that makes sense.

Oh on another note, not sure if you thought about this or not but when I was test driving and taking hard corners the bike would die for a second and then kick back on. At first I thought I was running out of gas because I was almost empty but after filling up and it still happening I realized it's the tilt sensor.

The bike doesn't lean in corners anymore and it's throwing the sensor over to one side and killing the ignition. So you'll need to remove your sensor and bypass it.

[ionbeam]

Youse guys adding fans need to keep an eye on amps management. The stock fans alone take the electrical system to the limits.

[Nitrotate]

Youse guys adding fans need to keep an eye on amps management. The stock fans alone take the electrical system to the limits.

So do you think the system is different than other yamahas that have twin fans? I would think it could handle 2 but I will definitely take your advise into consideration because I'm looking at doing 3.

[Nitrotate]

Oh, and I'm not necessarily running my fans through the "system" I'm direct connecting them to the battery and a toggle so I can have them on and off when needed...

[ionbeam]

Just throwing some things out here.

The primary radiator fan is normally turned on and off by the ECU that monitors the actual cooling system temperature using the sensor on the cooling rail above the valve covers. I assume that you will be leaving this system intact.

The Gen I has one cooling fan. The Gen I charging system is rated for a maximum output of 490 watts at 5k RPM; less RPMs than that and the stator output drops off significantly. The implication is that the cooling fan is most likely to turn on when RPMs are at the lowest, resulting in least available stator output. FWIW, Electrosport measured a Gen I charging system and they claim to have only measured a real 420 watts at 5k RPM.

I have used my amp probe to measure my Gen I's electrical system so I have some real numbers that should be typical of any Gen I. The clamp-on amp probe sends its output to a DMM where the current is read. In the picture below, my DMM is measuring the current leaving the R/R at idle with my heated grips on. It is showing ~33 amps = 442 watts. Since this was at idle the voltage at my battery terminal was around 13.4 volts. With this same setup, at idle with just the motorcycle, normal headlights and running lights I measured 20-22 amps of current = 280 - 308 watts.



The FSM doesn't actually specify the fan motor current so we need to ad-lib a bit. The Gen I fan is backed up by a 15 amp fuse. In most electrical systems the fuse will be roughly twice the expected nominal current. To be conservative, this means the fan motor will draw between 5-7 amps = 70-100 watts. Nominal current draw on my FJR was between 20 - 22 amps = 280 - 308 watts. Add to this the 70 - 100 watts of the radiator fan and we get a wattage bracket of 350 to 408 watts. This is without brake lights. If you are sitting at a traffic light at idle and the fan turns on, you electrical system will see a 350 - 408 watt load right when the stator is outputting the lowest amount of current. If you add another fan (best scenario 70 watts) or two fans (best scenario 140 watts) the charging system will be overwhelmed, the electrical system will be knocked down to battery voltage, and the battery will be supplying make-up current for the stator shortfall. The stator is also entering a zone where it can be permanently damaged.

Connecting any supplemental fans directly to the battery will not relieve the stator when electrical load exceeds the stator output current. I'm not promising stator damage, just mentioning that you are in a serious risk zone. You may get away with this condition until you tire of your spiffy toy -- or not. A volt meter will show you what is going on so you can monitor the health/deterioration of the electrical system. If you are aware that things are starting to go south you can manage the situation and not have to worry about walking home, you will almost always get early notice that the stator is beginning to fail. I'm sure you will be properly wiring any and all fans, so the only real risks are draining the battery and cooking the stator. Time to make risk/reward assessments. Unfortunately, adding a second battery will only cause the stator to work harder. There are not a lot of options to assist the low output of the Gen I's charging system.

Edit: An Electrosport stator is an option. Expect an ES stator to have roughly a 40k mile life, this is actually pretty good for a stator that makes 100 watts over the stock system, nearly a 25% power increase. The other real big buck option is to retrofit a Gen II charging system.

[nofreeride]

Thanks ionbeam. Always a wealth of technical information. So the point is to not add a lot (or none) of electrical load over the stock FJR. A few amps is all we really have to play with. Darn, I was thinking about adding heated grips.

A second battery could be added in a strategic location for weight distribution, and then NOT connected to the FJR's electrical system. Maybe hook up the reverse motor, a fan, lights, heaters, etc. Of course, it would have to be charged (a plugin hybrid?). On second thought, I don't like this idea. The point was to keep the weight and complexity down in the first place.

Besides the velocity of the air hitting the radiator, there shouldn't be any reason why the stock cooling system can't be made to work.

[Nitrotate]

Yeah good info that's appreciated! I was considering a second battery so maybe that's what I'll do.

[nofreeride]

Ok, here we go. The basic shape is all tacked in. I will add additional support and triangulation along with finish welding later. Then the body panels. But now, to work out most of the controls, front shocks, and dash.

 

 

 

[Nitrotate]

Sweet, moving along fast! Wish I had as much room as it looks like you do... Sure makes it easier to work on things. I did quite a bit of work on mine this weekend myself.

[cruppelt]

Woohoo! Looking great. Congrats!

[nofreeride]

Sweet, moving along fast! Wish I had as much room as it looks like you do... Sure makes it easier to work on things. I did quite a bit of work on mine this weekend myself.

Thanks. Sharing the shop with one of my neighbors, splitting the rent. It's about twice the size of what you see in the pictures. His is the lowrider stationwagon project.