GVW and Max load on touring Motorcycles

[sickpup]

I've been having problems over the last few years with one of the Deauvilles with the rear tyre sidewalls cracking. I've been in contact with the manufacturer of the tyres who initially put it down to low pressure.
A relatively new rear tyre has now gone the same way, one that has never had more than 2 psi low pressure and no punctures so I looked a little further into it and having discussed it with the tyre manufacturer it now appears the sidewall cracking has in fact been caused by overloading.

The Deauville is a heavy bike at 260kg or so and uses a 69 load rated tyre. The maximum load on the bike which surprised me is only 187kg for the ABS version which I have. This is for a bog standard bike. If you add the various extras such as top box and rack, belly pan, heated grips, hand deflectors, large pannier lids, handle bar muffs, blanket etc you are adding around 20kg weight which comes off the maximum load so instantly you are down to 167kg.
I weigh 118kg naked so add 12kg for clothing and helmet so once on the bike you are down to only 37kg for the pillion and any load in the panniers and top box. Just to save time I am overweight and could do with losing 15kg but I'm also big, just not weight lifter big
The boxes it is recommended only carry 5kg a piece but people tend to carry a lot more but lets assume 15kg for the lot and you are down to 22kg for the pillion.
My other half is 90kg dressed so that would overload the bike by 68kg

Both the ST1100 and the ST1300 have the same type of maximum loads so it is likely that 2 average sized people on any of these bikes would overload them, odd for bikes that are sold as two up tourers but also wipes out the lie that people buy these bikes to carry heavy loads.

I'm going to get around this problem by fitting a larger tyre with a 73 load rating, it'll give an extra 40kg in capacity on the rear tyre which should stop the sidewalls splitting and I'll have to stop carrying heavy luggage which shouldn't be a problem, I have a car now.

It surprised me just how low the maximum load was and just how marginal the overload capacity was on the tyres.

[MarJay]

I remember a column in one of the mags about this exact subject. I think it was one of those legal advice jobbies, but they were saying one of the older GSs has a very low maximum load, such that a larger gentleman with a medium sized pillion and the fashionable hard steel luggage would feasibly take it over the maximum load by about 50kg.

It's something hardly anyone checks, but I did not consider it to be an issue as I am very below average weight for a UK rider, and I never take pillions, but quite a few 'average' riders in the UK would do well to take it very seriously indeed.
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British beauty: Triumph Street Triple R; Loony stroker: KR1S; Track fun: GSXR750 L1; Commuter Missile: GSX-S1000F
Remember kids, bikes aren't like lego. You can't easily take a part from one bike and then fit it to another.

[sickpup]

[MCN]

My K1300GT
Says: Bike (90% fuel) 288kg (hevi bastirt.)

Permissable gross weight 520kg

Max payload 232kg.

I'm 101.5kg dripping wet (fat bastirt) geared up 115

Pillion 70kg (she's a fitty) geared up 85

I thing 10 kg in the panniers and 15 in the top box.

So I probably never had it over the OEM spec max weight.

It was running Metzlers Roadtec but stopped using them as they kept losing the hardband when there was still 2.5mm min tread.
I now use Michelin Road 6. Much better tyre. And I never bother trying to compare one major brand tyre with another I never push my bikes to the limit of the tyre.
I go by how long the last and how well the track.[/list]
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[sickpup]

[stinkwheel]

Never thought about that either. Although I'm aware my old bus is heavy so i fitted the GT version of the road 6 so I'm probably ok.

Having just checked, the GT and standard version have the same load rating of 73 (365kg).
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[DaddyStu]

I'm leaving for Bilbao in a few weeks on a Tracer loaded to max weight, maybe a bit over. Didn't expect to have to be weight weenie'ing but my 'little' boy is 85 bleedin' kg's now.

Yammy panniers are heavy AF even empty. Might get a cheap set of throwover saddle bags instead.

Trying to drop my weight - on the exercise bike every other day for past 4 months! Not so easy to shift the lard with middle-aged testosterone levels though.
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Daddystu
Zontes 125-G1 (part-ex'd). Yamaha Tracer 700.

[MCN]

I never considered the tyre being overloaded is the OEM recommended tyre and weights are used.

I only had a problem with the Metzelers on the big bike. I think the power delivery is too much for the metzeler.

I never had any tyre sidewall fail on any bikes. And I've took many to the rayon.

Under inflation overheats the tyre and sidewall suffers.

My K1300GT tyre pressure spec is 36psi front 42 psi rear.
Loaded or unloaded. So bmw don't consider tyre weight limit for the tyres they fit.
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[P.]

You've got me checking my RT now, which suggests 235kg max, myself and pillion combined is about 210kg so thats fine, but its never crossed my mind re the tyre rating... just checked and thats listed as 365kg.

My bikes apparently 260kg wet no panniers. Me + bike and a tent would be close. However is my weight shared between the 2 tyres? How does it determine the overall max load? I'm dumb in that respect.

[stinkwheel]

What'll really get you is what the loading on the front tyre under hard braking is.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[A100man]

Average UK weight is now abouy 85kg (13st 5lbs)men and 72 kg (11St 4lbs) women up about 5% in the past 20 years.

People are getting taller but that's quite some heft. I always figured 12 and 9 was about average. No wonder the wankpanzer GSs are so popular.
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Now: A100, GT250A, XJ598, FZ750

Then: Fizz, RS200, KL250, XJ550, Laverda Alpina, XJ600, FZS600

[sickpup]