# Burstner 747 /748 owners



## 92180 (May 1, 2005)

Spoke at length today to Mark Gibson at Michelin technical ,Stoke. 

Went over the tyre pressure issue on the MH. After giving him the axel weights of 2000kg front and 1500kgs rears and discussing max load at 5000kgs, and train weight at 5500kgs (Alko plate under bonnet) he calculated the following figures. 

Front 2000kgs loading pressure 4.10 bar (59.5psi) 
Rear 1500kgs loading pressure 3.0 bar (43.5psi) 

We went on to look at alternative loadings so the a comparison could be reached 

Front 1750kgs loading pressure 3.5 bar (50.8psi) 
Rear he said he would not reccomend below 3.0 bar (43.5psi) 

He thought that the best method was to take the MH to a weigh bridge and weigh the unit, then move it so they front wheels are of the bridge and recalculate. This would give the actual front and rear weights and by using the difference 2000kgs @4.1 and [email protected] you could divide the 0.6 bar by 250 kgs and calculate accordingly 

ie 1 kg = 0 .0024 bar (0.034psi) 

His suggestion is to load up with as much kit as usual , weigh it , split the axel weights and calculate the pressure. 

Mark was good enough to allow me to add his name to the information but it is in no way to be taken as anything other than a good starting point. 

I will be cahnge in line with the guidance and fine tuning once it has been on the weigh bridge.Accurate measurement must be used. 

Hope this is of some use.


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## BERTHA (May 21, 2005)

Don't the Burstner handbook quote 5.5bar on the front and 4.5bar on the tag axle tyres.

Why would they quote this is if it is wrong, sorry, not criticising your findings just makes one feel a little bit confused on who to trust

Regards
Hugh


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## 92180 (May 1, 2005)

I thought that as well Hugh and quoted the Alko book figures to Mark. 

His thought was that our european cousins maybe overload with a bit more regularity than us. 

When I have looked at other postings - Horsey who has a Euromobil tag is stating 4.5 and 3.5 bar for that. It might not have the same payload as the Burstner but it is nearer the Michelin tech ratings than 5.5 bar. 

I will give it a try and monitor tyre temp and wear pattern. 
At 5.5 the steering feel is quite strang --a bit like it has diff wind up. 

Are you running 5.5 ?


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## BERTHA (May 21, 2005)

Maybe I should keep and the higher rating has we travel around more or less at the Max limit of 5 ton

Let me/us know how you get on
Regards
Hugh


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## rft (May 4, 2006)

*Tyre Pressure*

As a 747 newbie I was wondering why you took the trouble to seek advice from Michelin. Have you had handling problems?


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## 92180 (May 1, 2005)

I personally have no problem with handling even at 80 psi all round. It is just a comfort issue with me. If they are overinflated it will , bounce more, have less traction in the wet taking off and wear out the tyre centre quicker. 

I am still confused with the outcome, both by what Alko state and what Michelin state. Further complications by the posting on Tech form . 

I have chosen to drop the rear pressures to that stated by Alko which was the same as Michelin but will use the front pressure from Michelin. If the tyres feel too warm when run I will increase pressure, same if unit feels as if it is oversteering on corners and roundabouts. 

We should keep this topic active and be willing to post pressures and handling comments. By doing that we might all find a happy medium.


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## 100836 (Sep 3, 2006)

just while we are on tyres, any idea how much milage i should get from the 747 michelin tyres and do the rears scuff out much or is it negligable

not overconcerned by tyre wear just interested really


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## fdhadi (May 9, 2005)

Not sure about wear yet (6,000 miles)

Tyre pressures for the 747 / 748 as quoted by Bürstner are 5.5 bar front & 3.5 bar rear. Much higher than this and you tend to bounce, although i do go to 3.8 bar in the rear when fully loaded.

Hope this helps.


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