Reverse Trike

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Just a quick update, I got the shifter done now too. Now I'm just trying to get the damn thing to stay running when I put it in gear. I know the kickstand and the clutch both have to be up/in and I've addressed that but it still kills the motor so I'm missing something somewhere. I'll find it I just need to get in there and start figuring it out.

 
The clutch doesn't have to be in to run, just to start (if starting in gear,) but the sidestand switch has to be correct. You can drop into first without the clutch and try to run, but it might be bad.

Correct decision tree for starting:

Starterflowchart.jpg


Carmakers have had to have a clutch switch starter interlock for decades, without regard to being in neutral. But the chart shows you that if it's in neutral, it doesn't care what the clutch and sidestand are doing. So it's running in neutral, you've got it clutched, and it dies when you drop into first. Has to be the sidestand switch. Once it's running that's the only switch that can kill it just by being in gear as opposed to neutral.

OR . . . . .

I assume you can push the thing around when it's in gear with the clutch depressed? If you don't have enough clutch action, you may be killing the motor from friction.

 
Ok yeah that's how I understand it and if there's no other mechanisms for killing it then I'll have to double check everything. I have the rear wheel suspended so it's not friction and yeah the bike will move with the clutch in and while in gear. I'm headed out now to take a closer look.

 
Ok yeah I just had a bad jumper wire hooked up so it still thought the kickstand was down. So that was my first test with the shifter and clutch and all! It works perfect!! The shifter is super smooth and easy to shift too. Basically one finger shifting. That push pull cable I used was from a boat supply place online and it worked out perfect.

Woohoo, now as soon as I get the radiator holes fixed and get it mounted I'm good to go for road testing!!! Can't wait!!

 
Thanks guys, it's pretty exciting! My big holdup now will be the radiator. I can't seem to find any used radiators on ebay and new they are like $400. First I'm going to run it down to a radiator shop to see if they think they can fix the holes and then we'll see but if I have to buy a new one then the cost will stop me in my tracks for a while until I can come up with the cash... :(

 
Good deal!!!! Glad you found it so quick. Now find a rad. I doubt they'll want to try to fix it.

Well the owner is a friend of a friend and he's the owner and also a former MRA racer and knows a lot about bikes so hopefully he can pull it off but if not maybe I'll try to find out if maybe an R1 radiator will work?? I've found R1 radiators for cheap and it doesn't have to bolt to the original spot anyway so mounting holes don't have to match...

 
..... but if not maybe I'll try to find out if maybe an R1 radiator will work?? I've found R1 radiators for cheap and it doesn't have to bolt to the original spot anyway so mounting holes don't have to match...
As long as it has the same volume and will allow enough air to pass through. I wonder if a small automobile radiator would work. It can't keep the engine too cool, there's a thermostat involved.....

 
..... but if not maybe I'll try to find out if maybe an R1 radiator will work?? I've found R1 radiators for cheap and it doesn't have to bolt to the original spot anyway so mounting holes don't have to match...
As long as it has the same volume and will allow enough air to pass through. I wonder if a small automobile radiator would work. It can't keep the engine too cool, there's a thermostat involved.....
Any type of heat-exchange medium may work. Routing the coolant through all that square-tubing frame may be enough...? :)

Seriously, this shouldn't be too hard to solve (given the roomy platform). A (any) radiator will probably suffice?

 
..... but if not maybe I'll try to find out if maybe an R1 radiator will work?? I've found R1 radiators for cheap and it doesn't have to bolt to the original spot anyway so mounting holes don't have to match...
As long as it has the same volume and will allow enough air to pass through. I wonder if a small automobile radiator would work. It can't keep the engine too cool, there's a thermostat involved.....
Any type of heat-exchange medium may work. Routing the coolant through all that square-tubing frame may be enough...? :)

Seriously, this shouldn't be too hard to solve (given the roomy platform). A (any) radiator will probably suffice?

I kind of figured so, the only concern I had was, is can the water pump move the fluid that far? In other words I actually wanted to route the radiator up to the front of the vehicle (approx. 9 feet away from the bike) but I'm not sure if the bikes impeller can move the fluid that far efficiently. Maybe it can simply because of the nature of "hydraulics" as long as there are no air pockets of course??? I don't know... anyone?

 
..... but if not maybe I'll try to find out if maybe an R1 radiator will work?? I've found R1 radiators for cheap and it doesn't have to bolt to the original spot anyway so mounting holes don't have to match...
As long as it has the same volume and will allow enough air to pass through. I wonder if a small automobile radiator would work. It can't keep the engine too cool, there's a thermostat involved.....
Any type of heat-exchange medium may work. Routing the coolant through all that square-tubing frame may be enough...? :)

Seriously, this shouldn't be too hard to solve (given the roomy platform). A (any) radiator will probably suffice?
I kind of figured so, the only concern I had was, is can the water pump move the fluid that far? In other words I actually wanted to route the radiator up to the front of the vehicle (approx. 9 feet away from the bike) but I'm not sure if the bikes impeller can move the fluid that far efficiently. Maybe it can simply because of the nature of "hydraulics" as long as there are no air pockets of course??? I don't know... anyone?
Hopefully..., an engineer-type will post-up and provide a well-reasoned answer. :)

Failing such a lucky intervention -- you can resort to "Lemon Engineering" (Suck it and See...). IOW, just do it. :blink:

 
Last edited by a moderator:
Awesome project!

As for the water pump, they are designed for a certain volume at a certain head pressure. If you maintain the height and piping diameter of the original system you should be able to locate a radiator almost anywhere on the frame. Once the system is full of fluid it will circulate at the pumps rated volume. You might consider locating the radiator such that you could capture heat for the cab in colder weather. The system should be thermostatically controlled bypassing the radiator until the desired operating temperature is achieved. This is, of course, assuming that with an enclosed cab you will ride this in a lot colder weather than you would a motorcycle.

 
Last edited by a moderator:
Awesome project!
As for the water pump, they are designed for a certain volume at a certain head pressure. If you maintain the height and piping diameter of the original system you should be able to locate a radiator almost anywhere on the frame. Once the system is full of fluid it will circulate at the pumps rated volume. You might consider locating the radiator such that you could capture heat for the cab in colder weather. The system should be thermostatically controlled bypassing the radiator until the desired operating temperature is achieved. This is, of course, assuming that with an enclosed cab you will ride this in a lot colder weather than you would a motorcycle.

Yes that's exactly why I wanted to move it up front (for cab heat). As far as the circulation comment, that's what I was wondering and keeping the hose diameter the same or possibly even a little smaller could potential keep the flow rate the same and still move it that far away from the pump and back sufficiently. I'll see if some more opinions come in, thanks guys!

 
Awesome project!
As for the water pump, they are designed for a certain volume at a certain head pressure. If you maintain the height and piping diameter of the original system you should be able to locate a radiator almost anywhere on the frame. Once the system is full of fluid it will circulate at the pumps rated volume. You might consider locating the radiator such that you could capture heat for the cab in colder weather. The system should be thermostatically controlled bypassing the radiator until the desired operating temperature is achieved. This is, of course, assuming that with an enclosed cab you will ride this in a lot colder weather than you would a motorcycle.

Yes that's exactly why I wanted to move it up front (for cab heat). As far as the circulation comment, that's what I was wondering and keeping the hose diameter the same or possibly even a little smaller could potential keep the flow rate the same and still move it that far away from the pump and back sufficiently. I'll see if some more opinions come in, thanks guys!
If you decrease the diameter of the hoses it will increase the velocity of the flow with a slight increase in the pressure. Thas will also effect the performance of the radiator. Higher velocity would mean less time in the radiator. Most coolent systems are designed for a rated flow not pressure. Something else I thought of after my last post was concerning the size of the radiator. If you go with a larger radiator you definitely want a thermostat especially if you want to take off heat. The larger the radiator the larger the heat exchange surface, so use the thermostat to maintain coolant temp not radiator size.

 
Awesome project!
As for the water pump, they are designed for a certain volume at a certain head pressure. If you maintain the height and piping diameter of the original system you should be able to locate a radiator almost anywhere on the frame. Once the system is full of fluid it will circulate at the pumps rated volume. You might consider locating the radiator such that you could capture heat for the cab in colder weather. The system should be thermostatically controlled bypassing the radiator until the desired operating temperature is achieved. This is, of course, assuming that with an enclosed cab you will ride this in a lot colder weather than you would a motorcycle.

Yes that's exactly why I wanted to move it up front (for cab heat). As far as the circulation comment, that's what I was wondering and keeping the hose diameter the same or possibly even a little smaller could potential keep the flow rate the same and still move it that far away from the pump and back sufficiently. I'll see if some more opinions come in, thanks guys!
If you decrease the diameter of the hoses it will increase the velocity of the flow with a slight increase in the pressure. Thas will also effect the performance of the radiator. Higher velocity would mean less time in the radiator. Most coolent systems are designed for a rated flow not pressure. Something else I thought of after my last post was concerning the size of the radiator. If you go with a larger radiator you definitely want a thermostat especially if you want to take off heat. The larger the radiator the larger the heat exchange surface, so use the thermostat to maintain coolant temp not radiator size.

Yeah good point. I'll just plant to stick with as close to the same size hose as possible and figure out a way to get a thermostat inline also. Thanks

 
You've already got a thermostat, which doesn't care how big the radiator is, only how hot the water is. Go TOO big on the radiator and the thermostat will spend more time closed than open, and maybe the water sitting in the rad is cool enough to close the thermostat pretty quick once it opens.

Heck, a couple of heater cores might be enough radiator for this thing, I don't know.

(BTW, if you do find a couple of small radiators and decide to use them, run them one after the other, so all the water goes through each. Don't try to split the flow, some to one and some to the other. You'll end up with backflow at a junction somewhere, and maybe ultimately no flow at all.)

 
Yeah I think what I'm going to do is see if that old toyota pickup I pulled the steering and suspension out of has a decent heater core and yank it out and then my father in law has another junk car up at his place that I could get another core from and just hook two of them up.

 
Yeah I think what I'm going to do is see if that old toyota pickup I pulled the steering and suspension out of has a decent heater core and yank it out and then my father in law has another junk car up at his place that I could get another core from and just hook two of them up.
My opinion:

the volume isn't going to be a problem, the weight of the water could be. Don't mount the radiator(s) any higher above the engine than the radiator is on a stock bike. The water pump would have to work hard to move the weight of the water vertically as opposed to merely circulating the coolant.

Is that "clear as mud"?

 

Latest posts

Top