4.7 vs 3.1 IMS for servicing the bike?

I'm about to order a larger tank & really only need more that the 3 gallon capacity for one or two rides a year.
I cold haul a rotopax easily instead of buying the larger tank if there is an advantage to it for servicing access or?

Thanks,
Buddy

I went with a 3.1 gallon early on and then picked up the 4.7 for a trip out west. My original plan was to sell the 4.7 once I got done with the trip but instead I opted to sell the 3.1 since the 4.7 worked out so well for me.

I think the bike handles much better with it loaded than with a 3.1 gallon tank and a couple of gallons hanging on the rear of the bike taking up space that I would probably use for gear on my long rides.

I love my 4.7 IMS.  The range supports focusing on the ride and not looking for gas!

BTW, I bought a first production IMS, which leaked gas on the bottom of the wings.  I contacted IMS and they shipped a 2nd generation tank-improved fasteners on the wings-at no cost to me.  

I am super pleased with my IMS 4.7 tank!    

Thanks, I like the radiator protection from the larger tank as well.

I went with the 4.7 for a while & replaced it with the 3.1.
My logic is I have better fuel range (easy 160 miles) than most anyone I ride with using the 3.1, I don't like the width of the 4.7 for my legs or for tight single track,
 I never really trusted the vacuum pump setup for getting fuel to the mail pump, which meant I was often carrying a gallon or so more fuel than I needed to be sure I didn't have an issue. A 1.75 gallon Rotopax carries easily for a Death Valley or similar trip & I have more confidence in being able to use it all.

I bought the 4.7 for the radiator protection, but it doesn't work in real life. The tank is designed to be able to move slightly and will rock right into the radiator. It will help prevent it from springing leaks, but the radiator fan will still get shoved into the radiator damaging the fan. I know from experience.

If the 3.1 gal tank is narrower I would go with that over the 4.7 if you do aggressive offroad and save some cash, that is assuming you don't need the extra range of course.
Ive only had it for 3k miles, but the vacuum pump system works very well, i test it almost every week. I am nervous about the fact that the fuel pump is exposed to extra heat by not being submersed in fuel. These pumps are known to overheat and fail, but I am past 10k on the original pump, so I hope the pump failure issue is just blown out of proportion by the web.

beee wrote:

I bought the 4.7 for the radiator protection, but it doesn't work in real life.  The tank is designed to be able to move slightly and will rock right into the radiator.  It will help prevent it from springing leaks, but the radiator fan will still get shoved into the radiator damaging the fan.  I know from experience.

If the 3.1 gal tank is narrower I would go with that over the 4.7 if you do aggressive offroad and save some cash, that is assuming you don't need the extra range of course.
Ive only had it for 3k miles, but the vacuum pump system works very well, i test it almost every week.  I am nervous about the fact that the fuel pump is exposed to extra heat by not being submersed in fuel.  These pumps are known to overheat and fail, but I am past 10k on the original pump, so I hope the pump failure issue is just blown out of proportion by the web.

I suspect the pimp issue has something to do with tolerance stack up. Most pumps are made with parts near the center of the specification and things work well. But a few pumps are made with Part A at one side of the spec and Part B at the other side of the spec and then you begin to have problems.

I kept my Flatland Radiator guard on my bike when I installed the 4.7L tank. It does make contact with the tank but I cut a bit of heavy duty inner tube and tie strapped that to the guard. So far so good.

Guess I can probably honestly say that I have no clue if the vacuum pump works on mine. When we were out in CO whenever the bikes with the short legs would fuel up I would do likewise - even though I may not have needed it. My logic is shit happens - better to have extra gas and not need it than to need it and not have it.

I'm not dissing the 4.7, I never had any problems with it. I found myself carrying/filling the tank with more fuel just because I had some concerns about being able to access the last gallon.

I like the narrower tank & the simplicity of the 3.1. The low fuel light typically comes on ~140 mile mark & leaves me with ~40 mile reserve. Most of my riding buds are getting pretty nervous ~100 miles anyway so more than 3.1 gallons was just not needed for my normal rides. With the 1.75 Rotopax. I should safely make 245 miles before the low fuel light comes on (the second time). I typically get in the low sixties fuel economy riding off road.

4play wrote:

I'm not dissing the 4.7, I never had any problems with it. I found myself carrying/filling the tank with more fuel just because I had some concerns about being able to access the last gallon.

I like the narrower tank & the simplicity of the 3.1. The low fuel light typically comes on ~140 mile mark & leaves me with ~40 mile reserve. Most of my riding buds are getting pretty nervous ~100 miles anyway so more than 3.1 gallons was just not needed for my normal rides. With the 1.75 Rotopax. I should safely make 245 miles before the low fuel light comes on (the second time). I typically get in the low sixties fuel economy riding off road.

No worries.. In fact I semi panicked when got the 4.7 for the COBDR. In retrospect my 3.1 gallon IMS tank on the WRR would have been able to make that trip.