Reply
 
Thread Tools Search this Thread
 
Old 07 January 2012, 08:43   #1
Member
 
Country: UK - England
Length: no boat
Join Date: Jun 2011
Posts: 543
Tyre Pressure

Does anybody know what the correct tyre pressure should be on my twin axle SBS that is carrying an Osprey Viper Max? One tyre has a reading of 28psi, the other three vary in pressure but are less than that. Thanks.
__________________
Will.

"By skill not force."
Silverfox is offline   Reply With Quote
Old 07 January 2012, 08:59   #2
Member
 
Country: UK - England
Town: Plymouth
Length: 6m +
Join Date: Mar 2011
Posts: 2,693
I don't know but it will say on the tyre wall what it's rated to.

Peter ~ Boatsandoutboards4sale ~ askboatsandoutboards4sale@sky.com ~ 07930 421007
__________________
Boats&Outboards is offline   Reply With Quote
Old 07 January 2012, 09:00   #3
Member
 
hadd's Avatar
 
Country: UK - England
Town: Manchester
Boat name: "mr Jingles"
Make: Ribcraft
Length: 5m +
Engine: 130 Etec
MMSI: 235074968
Join Date: Jun 2009
Posts: 1,401
RIBase
Quote:
Originally Posted by Silverfox View Post
Does anybody know what the correct tyre pressure should be on my twin axle SBS that is carrying an Osprey Viper Max? One tyre has a reading of 28psi, the other three vary in pressure but are less than that. Thanks.
Hi silverfox, It should say on the side of the tyre what pressure should go in there , my tyres take 60psi i always put 55psi in them
__________________
hadd is offline   Reply With Quote
Old 07 January 2012, 09:13   #4
Member
 
Country: UK - England
Length: no boat
Join Date: Jun 2011
Posts: 543
The tyre wall on my car tyre is rated way above the 32psi that are in them, as 32 is what the manufacture recommends. Is it right therefore to go to nearly the max rated psi of the tyre? Won't the trailer be very bouncy when towed?
__________________
Silverfox is offline   Reply With Quote
Old 07 January 2012, 10:07   #5
Member
 
AMac's Avatar
 
Country: UK - Scotland
Town: Dunoon
Boat name: Celtic Wanderer
Make: Ribcraft
Length: 9m +
Engine: Volvo D6, Honda
MMSI: 235087784
Join Date: Nov 2011
Posts: 205
the trailer manufacturer will be able to give you a pressure if you tell them the weight of the load being carried on the trailer
__________________
AMac is offline   Reply With Quote
Old 07 January 2012, 10:21   #6
Member
 
Country: UK - England
Town: Plymouth
Length: 6m +
Join Date: Mar 2011
Posts: 2,693
Trailer guy will give you definitive advice but generally when towing any distance (ie motorway) with tubeless tyres you want them to be inflated quite close to max rating. This helps preventing them from heating up which gives a greater risk to blowout, shredding etc. If they are under-inflated they become weaker on the tyre walls. Even some of the smaller 10 inch wheels are inflated past what a car needs.

Peter ~ Boatsandoutboards4sale ~ askboatsandoutboards4sale@sky.com ~ 07930 421007
__________________
Boats&Outboards is offline   Reply With Quote
Old 07 January 2012, 10:56   #7
RIBnet admin team
 
willk's Avatar
 
Country: Ireland
Length: 4m +
Join Date: Feb 2008
Posts: 14,898
My SBS 2000 came with crappy Comac tyres, I had a twin motored 6.5m on it and ran the tyres around the 40psi mark. I was never towing over 50mph for any time and I never found any warming (or bouncing). I'd agree with checking it with SBS....
__________________
willk is online now   Reply With Quote
Old 07 January 2012, 11:14   #8
Member
 
Leapy's Avatar
 
Country: UK - England
Town: Sheepy Parva
Boat name: Sadly Sold
Length: no boat
Join Date: Sep 2008
Posts: 1,731
Having weighed my RC5.3 and had a shock the wheels and tyres were uprated with - for a trailer - some sexy looking low profile jobbies rated at 96psi which is what I was told to run them at.

I actually run them at 85psi and no problems though the 12v tyre pump has a tear in it's eye everytime it sees the trailer.
__________________
Leapy is offline   Reply With Quote
Old 07 January 2012, 12:16   #9
Member
 
Country: UK - England
Length: no boat
Join Date: Jun 2011
Posts: 543
Thanks everybody for you assistance. I think my 12v pump is going to also wince like Leapy's very soon!
__________________
Silverfox is offline   Reply With Quote
Old 07 January 2012, 13:06   #10
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
Hi Silverfox

As B&O suggested, you need to keep on top of your trailer tyres, especially if you're towing good distances. Obviously it'll affect the towing characterisctics, but under inflated tyres will also have a greatly detrimental effect on your fuel consumption

TBH, your tyre rating will all be down to your tyre type / size / rating. Here's a previos post on identifying the spec of your tyres: http://www.rib.net/forum/f49/trailer...cky-44849.html

As suggested, SBS should be able to guide you. However, they sometimes put the psi rating on the chassis plate too, so that may be worth a check. You should find it n/s front on the drawbar / a-frame. As others have said, the rating should also be on the tyre too. It'll say something like "60psi cold", or similar. Check there too.

If you don't get any joy let me know the tyre info and I'm sure I'll be able to assist.
Trailer Guy is offline   Reply With Quote
Old 07 January 2012, 13:39   #11
Member
 
Erin's Avatar
 
Country: UK - Channel Islands
Town: A large rock
Boat name: La Frette
Make: Osprey Vipermax
Length: 6m +
Engine: 200 Suzzy
Join Date: May 2004
Posts: 2,893
I've always wondered whether it makes any difference as to whether you set the pressure when the trailer is laden or unladen. Presumably with a loaded trailer there is more weight and compression on the tyre resulting in an increased air pressure within? Or is the difference so negligible that it makes no odds?
Erin is offline   Reply With Quote
Old 07 January 2012, 13:41   #12
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
Have now added some common tyre pressures to this page:

http://www.rib.net/forum/f49/trailer...tml#post437589
Trailer Guy is offline   Reply With Quote
Old 07 January 2012, 14:14   #13
Member
 
mick's Avatar
 
Country: UK - England
Town: Wakefield
Boat name: Bouncer
Make: Redbay Stormforce
Length: 6m +
Engine: 2x Honda 100 Hp
MMSI: 235025718
Join Date: Jun 2009
Posts: 4,177
I am on 10 " 8 ply I haven't chequed them yet but reckon about 60 psi should do.
__________________
mick is offline   Reply With Quote
Old 07 January 2012, 14:16   #14
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
5.00 x 10 8ply?
Trailer Guy is offline   Reply With Quote
Old 07 January 2012, 14:19   #15
Member
 
mick's Avatar
 
Country: UK - England
Town: Wakefield
Boat name: Bouncer
Make: Redbay Stormforce
Length: 6m +
Engine: 2x Honda 100 Hp
MMSI: 235025718
Join Date: Jun 2009
Posts: 4,177
Quote:
Originally Posted by Trailer Guy
5.00 x 10 8ply?
Correct.
__________________
mick is offline   Reply With Quote
Old 07 January 2012, 14:24   #16
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
If they've a load index of 84 then their max capacity (@ 100kph) is 900kg and their max psi is 65. Ergo, you were bang on with your 60psi average - though I'm sure you were never in doubt!
Trailer Guy is offline   Reply With Quote
Old 07 January 2012, 14:27   #17
Member
 
mick's Avatar
 
Country: UK - England
Town: Wakefield
Boat name: Bouncer
Make: Redbay Stormforce
Length: 6m +
Engine: 2x Honda 100 Hp
MMSI: 235025718
Join Date: Jun 2009
Posts: 4,177
Quote:
Originally Posted by Trailer Guy
If they've a load index of 84 then their max capacity (@ 100kph) is 900kg and their max psi is 65. Ergo, you were bang on with your 60psi average - though I'm sure you were never in doubt!
Well i am a good guesser not sure if there cross plys as well
__________________
mick is offline   Reply With Quote
Old 07 January 2012, 14:31   #18
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
Quote:
Originally Posted by Erin View Post
I've always wondered whether it makes any difference as to whether you set the pressure when the trailer is laden or unladen. Presumably with a loaded trailer there is more weight and compression on the tyre resulting in an increased air pressure within? Or is the difference so negligible that it makes no odds?
I've often wondered myself Erin! I guess, theoretically, there could be a change in pressure, due to additional load, but it's likely compensated for by the deformation of the tire. Therefore the actual internal volume doesn't change (ergo pressure) as the tyre compensates for it.

Theoretically anyway! lol Doubtless there'll be someone along, far more astute than the pair of us, to correct us in a minute
Trailer Guy is offline   Reply With Quote
Old 07 January 2012, 14:34   #19
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
Quote:
Originally Posted by discomick View Post
Well i am a good guesser not sure if there cross plys as well

Yes sir, the 5.00 x 10 denotes cross ply. If they said 145R10 then the 'R' would indicate radial.
Trailer Guy is offline   Reply With Quote
Old 08 January 2012, 23:22   #20
CJL
Member
 
CJL's Avatar
 
Country: UK - England
Town: London/Oxford
Make: Ribcrafts
Length: 5m +
Engine: 150hp/2x115hp
MMSI: 235090215
Join Date: Oct 2002
Posts: 2,250
RIBase
Send a message via Skype™ to CJL
SBS Manual - http://www.sbstrailers.co.uk/pdf/Service_Manual.pdf

Tyre pressures on page 3.

Chris
__________________
www.northernexposurerescue.org.uk - A registered charity supporting sports and community events across England and Wales
Also why not check out the Ribcraft Owners Group?
CJL is offline   Reply With Quote
Reply


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




All times are GMT. The time now is 19:12.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.