Flourman’s Grand Design Momentum 21g Build

Every time we move, I vote for Denver. So far, I’ve got Cleveland OH and Stockton CA… To be fair though, they are both great in their own way. Cleveland has great food (not much else to do) and the weather in the summer is awesome. Stockton is 2h or less from Tahoe, Yosemite, San Francisco, Napa, Sonoma, etc. Still, I’m going to push harder for Denver next time.
It's #1 on my list to move to as well. Wife says no. One day....but till then Michigan isn't all that bad.
 
Great setup! I just sold my Reflection 5th wheel and ordered a 2022 Momentum 23G. It's scheduled to roll off the assembly line in the middle of November. My first upgrade will be either Battle Borns or Lion Energy LiFePO batteries. Do you mind sharing pictures on how you rerouted your battery cables to the storage cabinet?

Thanks!
 
Great setup! I just sold my Reflection 5th wheel and ordered a 2022 Momentum 23G. It's scheduled to roll off the assembly line in the middle of November. My first upgrade will be either Battle Borns or Lion Energy LiFePO batteries. Do you mind sharing pictures on how you rerouted your battery cables to the storage cabinet?

Thanks!
A little difficult to see but I took a hole saw through the one outdoor storage cubby. The wall is double layered (there is about a 2” air gap) there and goes directly to the area behind the converter/fuse panel. Everything runs through this hole (inverter 110v power back to the breaker panel. I did it this way because I wanted to keep the battery on the tongue separate from the house battery. The only thing the tongue battery handles is the electric jack and generator starting.

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We are out camping or I’d pull the converter out and take a picture there.

I used some 6AWG, 2-conductor cord that I ordered online somewhere. As I’m finding, that cubby holds temperature decent enough to allow the batteries to charge when the outside temp is below freezing. Coldest that compartment got last night was 41 and it was about 18 out this morning. Without a fancy battery heater or the new battleborn’s that heat themselves I wouldn’t have been able to charge at first light this morning.
 
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Great post, I will make a similar one later this week hopefully. Picking up a new Outdoors RV 23DBS. General plan is 500w of solar, 3-400Ah of lithium battery, a 3000w inverter, easy start, Sterling B2B, and some other creature comforts. I’ve built a van out before and I’m excited to do a TT. I would look into a DC to DC charger. Sterling is relatively inexpensive, smart alternator compatible, and will charge at 60A. They also make a 120A version but the price hike is substantial. The rest of my system will be Victron.
 
First pull with the Tremor! Tows so much better than my F150 from a stability and ride standpoint. The 3.5EB in my F150 seemed to have a bit more grunt but I’ve just got to get used to punching it vs easing into the 7.3. That 7.3 LOVES the R’s pulling the passes. 5500RPM like nothing. Trans Braking took a bit to learn but after about 45 minutes it was doing a great job holding speeds going downhill.

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Quite a bit of back end squat? Any idea what your tongue weight is? I’m guessing it will be similar to the ORV I have ordered- 1200-1300lb?
 
I’ve had a couple 4-strokes but the bee knees for 90% of what we do in Colorado and Utah are 300 2-strokes. They have the weight down low, are super torquey for a 2-stroke, resist flame out and are a bit lighter overall and that’s right out of the box. The 350 4-strokes are about the closest one can get to a 300 2-stroke but even there, they run hot and need a auto clutch or a lot of clutch skill.

The 300’s can about rev to zero and still come back from it. 4-strokes will flame out and make for a rough day on the trails.
Sorry for the multiple replies. Reading your post backwards lol. Also have a TE300i and the wife just sold her XCW150. Headed to 5 miles of hell next Friday. Hopefully it’ll be the shakedown trip with my TT.
 
Sorry for the multiple replies. Reading your post backwards lol. Also have a TE300i and the wife just sold her XCW150. Headed to 5 miles of hell next Friday. Hopefully it’ll be the shakedown trip with my TT.
Hahaha. We are headed to Moab next Thursday.

No problem with the multiple posts. The picture was with the whole setup pointed a bit downhill but the Momentum’s are tongue heavy. I’m guessing I was around 800-900lbs on the tongue. I barely had anything on my WD bars. I had set it up loaded a few weeks ago and I got all of my numbers good but I could feel I need to move them up a notch.

As far as the DC-DC, the Renogy controller is a DC-DC plus solar in one package. As for another DC-DC when pulling, I really don’t see a need for that with a generator and when I eventually get to putting solar on the roof.

The roof solar will be going through a Victron controller. I was pretty excited after running the heater last night and waking up to 62% battery, the 200W suitcase more or less replaced it all today. The MPPT controllers are legit.

Sounds like we have similar interests, might need to hit the trails sometime soon!
 
A little difficult to see but I took a hole saw through the one outdoor storage cubby. The wall is double layered (there is about a 2” air gap) there and goes directly to the area behind the converter/fuse panel. Everything runs through this hole (inverter 110v power back to the breaker panel. I did it this way because I wanted to keep the battery on the tongue separate from the house battery. The only thing the tongue battery handles is the electric jack and generator starting.

View attachment 36793

We are out camping or I’d pull the converter out and take a picture there.

I used some 10ga, 2-conductor cord that I ordered online somewhere. As I’m finding, that cubby holds temperature decent enough to allow the batteries to charge when the outside temp is below freezing. Coldest that compartment got last night was 41 and it was about 18 out this morning. Without a fancy battery heater or the new battleborn’s that heat themselves I wouldn’t have been able to charge at first light this morning.

Got it. That's awesome that the compartment is heated, it'll save me a few bucks by not having to go with the heated Battle Borns. If i'm not mistaken, I think 10ga wire is limited to 30A. Careful to not overload it.

Thanks for sharing and enjoy your camping trip!
 
Hahaha. We are headed to Moab next Thursday.

No problem with the multiple posts. The picture was with the whole setup pointed a bit downhill but the Momentum’s are tongue heavy. I’m guessing I was around 800-900lbs on the tongue. I barely had anything on my WD bars. I had set it up loaded a few weeks ago and I got all of my numbers good but I could feel I need to move them up a notch.

As far as the DC-DC, the Renogy controller is a DC-DC plus solar in one package. As for another DC-DC when pulling, I really don’t see a need for that with a generator and when I eventually get to putting solar on the roof.

The roof solar will be going through a Victron controller. I was pretty excited after running the heater last night and waking up to 62% battery, the 200W suitcase more or less replaced it all today. The MPPT controllers are legit.

Sounds like we have similar interests, might need to hit the trails sometime soon!
Definitely man!
 
Got it. That's awesome that the compartment is heated, it'll save me a few bucks by not having to go with the heated Battle Borns. If i'm not mistaken, I think 10ga wire is limited to 30A. Careful to not overload it.

Thanks for sharing and enjoy your camping trip!
I was completely wrong. It’s 2-conductor 6AWG which should handle 70A for under 10 feet with less than a 3% voltage drop.

As for the compartment, it’s not heated but it does get some “leached” heat from the camper. The heater duct runs on one wall of it.

I think if it was sustained, sub-freezing, it would cool off in there.
 
Quite a bit of back end squat? Any idea what your tongue weight is? I’m guessing it will be similar to the ORV I have ordered- 1200-1300lb?
Update after adjusting the WD hitch. It definitely rode and towed better with the hitch lighter. I’ll take the little bit of squat. The truck level gauge was just about the same. It was a solid 1 degree with the lighter setting, between 0-1 with the bars set heavier. Granted, I emptied the fresh tanks (had about 50 gallons in the picture). It may be a weird in between and maybe with 100 gallons in the fresh, I’ll need the heavier setting.
 
Up and over the passes to Moab we went for a 3-day dirt bike trip! Sure let the 7.3 eat. I’m sure at a few points I heard a big WHOOSH as that motor sucked the gas! Couldn’t be more happy!
 
Outdoors RV never ended up showing up at the dealer so I also bought a momentum 21g. Looking forward to doing the electrical. I think I’m going to put a battleborn gc3 (270ah) in the cubby as well. I like your idea of keeping the other battery for the generator and tongue, but how are you charging it?
 
Sorry for the multiple replies. Reading your post backwards lol. Also have a TE300i and the wife just sold her XCW150. Headed to 5 miles of hell next Friday. Hopefully it’ll be the shakedown trip with my TT.
Did you end up going to 5MOH? That is an amazingly fun trail!!
 
Did you end up going to 5MOH? That is an amazingly fun trail!!

Not this year yet! If weather holds we’re thinking potentially the first week of December. It’s a great trail though! We usually do it once a year at least. Last fall we did it as an out and back and it crushed my forearms lol.
 
Outdoors RV never ended up showing up at the dealer so I also bought a momentum 21g. Looking forward to doing the electrical. I think I’m going to put a battleborn gc3 (270ah) in the cubby as well. I like your idea of keeping the other battery for the generator and tongue, but how are you charging it?
The onboard converter charges both the tongue battery and the house battery (connected in parallel). It charges with a normal lead/acid charging profile. The DC-DC/solar charger then will take that and change the profile for Li. When running off solar, when the Li is full, the DC-DC/solar then trickle charges the tongue battery.

I did have to bump up the float voltage on my converter to keep the Li batteries charged when on shore power.

On another note, dirt bikes, 21G’s and Tremor’s. We may have to call each other to make sure we aren’t wearing the same shirts . 😂😂
 
The onboard converter charges both the tongue battery and the house battery (connected in parallel). It charges with a normal lead/acid charging profile. The DC-DC/solar charger then will take that and change the profile for Li. When running off solar, when the Li is full, the DC-DC/solar then trickle charges the tongue battery.

I did have to bump up the float voltage on my converter to keep the Li batteries charged when on shore power.

On another note, dirt bikes, 21G’s and Tremor’s. We may have to call each other to make sure we aren’t wearing the same shirts . 😂😂
🤣🤣🤣🤣🤣👍
 
Been a while since an update. The 2-way (120V/propane) fridge died. Every time you’d open it, the ammonia smell would about knock you over.

Picked up a Norcold DC only fridge. The DC only fridges have less space occupied by the propane tower so in a 6cu-ft space for a 2-way fridge, you can fit an 8cu-ft DC fridge. It was a super easy install but I’ve (my wife) got some finish carpentry to do.

The fridge pulls about as much as our ARB cooler does so I have no questions that my battery and solar system will keep up. It gives piece of mind when traveling (running the fridge vs. letting the propane burn for the fridge while on the road) and it should work better in warmer camping periods.

I took the opportunity to insulate a bit more around the fridge. Even though it had some insulation around the old fridge, I could still feel a little bit of breeze around it when that side was facing the wind.

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