Reply
 
Thread Tools Search this Thread Display Modes
 
Old 03-19-2010, 01:47 PM   #21
Admiral

 
ss3964spd's Avatar
 
Join Date: Jul 2009
Location: Fairfax Va
Posts: 1,512
Send a message via Yahoo to ss3964spd
Default

140 - I'm surprized that rig isn't all over the place when towed IM.

I don't know enough about trailering to say for sure but I doubt that the tri ax trailer is mitigating the need for more tongue weight. If I were to guess I'd say some other factor, or combination of, is keeping it in line. Are the tires all wearing evenly? With only 140 on the ball, does it make a lot of noise/clanking from the ball constantly being loaded/unloaded by the hitch?

Regardless, if it tows fine I'd see about cutting some length off the bunks then slowly back away from it and leave it alone. Maybe the folks on THT will have some more insights.

Dan
__________________

ss3964spd is offline   Reply With Quote
Old 03-25-2010, 09:10 PM   #22
Lt. Commander

 
Join Date: Jun 2007
Location: S.Wales
Posts: 218
Default

Not sure where in World you are (hint to update your profile) ...... just watch that change in position has not put too much weight on hitch.
Different rules in different countries .. in UK you should adjust boat on trailer to get between 50 - 100Kg down force on hitch. (nose weight)
__________________

Argonaut is offline   Reply With Quote
Old 03-25-2010, 09:51 PM   #23
Lt. Commander
 
Nimh's Avatar
 
Join Date: Jun 2009
Location: Puget Sound, WA
Posts: 180
Default

Quote:
Originally Posted by Argonaut View Post
...in UK you should adjust boat on trailer to get between 50 - 100Kg down force on hitch. (nose weight)
It's just a static measure instead of a percentage, regardless of overall weight? Is there a limit to max speed then also? With my boat that little tongue weight would make it wander dangerously at anything over residential speeds.
__________________
Jim and Angie
2005 Maxum 2400 SE
5.0L MPI with Bravo 3

Nimh is offline   Reply With Quote
Old 03-25-2010, 10:32 PM   #24
Lt. Commander

 
Join Date: Jun 2007
Location: S.Wales
Posts: 218
Default

In UK and (all of Europe) standard rules are hitch weight must be between 50kg and 100kg irrespective of weight.
It makes sense to us as car suspension is set up for balkanced car handling ... put more than 100kg on rear and it upsets balance .... especially under braking.
I think in US they use a % of trailer weight ........ which means you could end up with a hell of a lot of nose weight if towing a big boat.
Argonaut is offline   Reply With Quote
Old 03-25-2010, 10:44 PM   #25
Lt. Commander

 
Join Date: Feb 2010
Location: Half Moon Bay, CA
Posts: 152
Default

Argo: thanks for the suggestion, profile updated. Won't be trailering to the UK anytime soon, not that I wouldn't like to. 100KG = 220 lbs, yes? I'm at 140 lbs, so I'd be OK there. The guidelines I've seen here from the manufacturer and other places seem to be all over the map, but all fall within 5% to 15%, which would be 500 lbs to 1500 lbs in my case. 1500 lbs seems like WAY too much to me. Tow vehicle is a Dodge Ram 3500 Diesel dually, though - big truck.

At any rate, the boat has been moved forward and tomorrow I'll be re-measuring the tongue weight. Hoping one of these days I can stop worrying about trailer adjustments and actually get the boat in the water!
iceman is offline   Reply With Quote
Old 03-26-2010, 09:00 AM   #26
Lt. Commander

 
Join Date: Jun 2007
Location: S.Wales
Posts: 218
Default

That was my view .... 10-15% of a couple of ton of boat is a lot of nose weight .......if you brake that can cause a lot of down force on rear of tow vehicle .
Which could cause instability.
Argonaut is offline   Reply With Quote
Old 03-28-2010, 05:05 AM   #27
Lt. Commander
 
Nimh's Avatar
 
Join Date: Jun 2009
Location: Puget Sound, WA
Posts: 180
Default

I've towed no more than 15k pounds behind a Dodge 2500 V10 longbed extra cab... but I've always been under the impression tongue weight was a function of physics. I've towed travel trailers, fifth wheel RV's and half a dozen boats. While I respect following local laws, I'm puzzled by your point Argonaut. If you're towing a vessel so large that applying the brakes upsets the stopping power of that vehicle, I'm willing to imagine you're exceeding the mfg tow rating of the tow vehicle. Add a weight distribution bar system or a sway control system and things change dramatically. It's also not a function of simple percentage - hitch location, number of trailer axles and hitch location all play a part in balancing your load safely. Rule of thumb is for me is 10-12%

Iceman... some articles for your review.

http://www.howstuffworks.com/auto-pa...gue-weight.htm

http://www.sherline.com/lmbook.htm#refrn9

http://auto.howstuffworks.com/auto-p...ue-weight1.htm

http://www.boatered.com/forum/topic.asp?TOPIC_ID=121969

http://changingears.com/rv-sec-calc-...eight-tt.shtml

I used a local Washington State Patrol weigh station to get GVW and fine tuned our setup so we stop quickly and don't sway coming down hills at speed. The State Patrol was very helpful and exceeding professional. We tow 75 miles each direction to get our boat wet.
__________________
Jim and Angie
2005 Maxum 2400 SE
5.0L MPI with Bravo 3

Nimh is offline   Reply With Quote
Old 03-28-2010, 09:47 AM   #28
Lt. Commander

 
Join Date: Jun 2007
Location: S.Wales
Posts: 218
Default

MY setup is adjusted to give a nose weight of 75kg.

Assume a 3000kg rig ... (~3ton) If I went at 15% of gross laden weight ... I would adjust so I would be putting 450kg down force on the hitch ............. first off I could not lift up 450Kg ... so if jockey wheel failed I could not be able to add or remove trailer.

In my case I don't tow 3 ton so that is not so much of issue ...............

Logic to me would suggest that ideal is if trailer is balanced so weight is even on axles, with just enough weight to keep a constant load on hitch.

Why would you want to transfer 450Kg of download to rear of tow vehicle ? .... when trailer axles could take that load ? ... makes no logical sense to me.


As I said I mentioned that this is the law is Europe ...... I know US do not use this.
All the vehicles manufacturers/importers in Europe have to publish recommended max nose weight ... and all are in the 50-100Kg range (only have the data for non-commercial vehicles)
So the big US companies of Ford & GM ... also state this max loading.

As to my view ... if I had a car with 450kg pushing down on rear axle, by the laws of physics that means that the front wheels are having an upforce from the road ............ in heavy braking the forces will move (laws of physics) ... to me that makes balance of load to car wheels uneven. Sounder logic to have load balanced.

If you doubt the laws of Physics.
Balance a ball on a flat surface in or on your car & accelerate (or brake) ....... ball will move backwards under acceleration and forward under braking.

However as I pointed out if you are not in Europe the rules are different
__________________

Argonaut is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 07:32 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.