Archive of BMW Motorrad Club Cape (2006 - 2019)

Hey Anne Just a few minutes ago I [http://www.bmwmotorcycleclubcape.co.za/links/submit approved a link] that talks about tyres and tyre pressures ([http://www.bmwmotorcycleclubcape.co.za/links view the links]) It says for gravel reduce tyre pressure by 40% (for tubed tyres) or 30% for tubeless. For hard rock increase the pressure by 10%. I generally take mine down to 1.4 bar from 2 bar, unless it is thick sand in which case I go down to 1.1 bar. If the section has good gravel and some tar I take it to around 1.6 bar. HTH - what do others do? (BTW, I weigh 65kg and ride a '98 Funduro F650 with TW45s on. ;-) Website Administrator

Ek blaas die band af en trap die tyre met my voet todat daar slegs 'n effense beweging is . Dit werk vir die Dakar - weet nie of dit sal werk op die tubeless bande. Ek is meer "versigtig" vir klippe/rotse wat 'n lekband (of skade) kan veroorsaak as 'n effens te stywe band! Op die 650Gs/Dakar se onderstel, daar waar die ketting is, behoort instruksies te verskyn. Ek glo dit sal op die groter GS'e ook iewers verskyn. Groete

Dirt road pressures: I found that 1.5bar front and back works well for my 1150GS (tubeless) on average dirt road (eg when you dont know what lies ahead). If lots of sand, then 1.2 at the back and 1.5 front. (note: very very seldom as low as 1.2bar ---- I do not like very low pressures (or sand) in any case. If I carry a pillon or lots of luggage, I raise front and back by 0.2 bar (ie 1.7 front, 1.7 back) If both pillion and luggage, raise back another 0.2 bar (ie 1.7 front, 1.9 back) General rules of thumb as given by Charles sound correct, although the actual pressures I use, work out to be bit softer than their recommendation. Doing short distances with soft tyres on tarmac is OK, but keep speed down, inflate as soon as possible. Doing short distances on dirt road with tarmac pressure is also OK, provided you remember that yr grip is much less than with softer pressures. And be wakker --- it will help saving your mirrors from damage Wet weather - same pressures, reduce speed, increase awareness. Get yourself an analog (non-digital) tyre pressure gage (Midas etc has reasonable ones from R60. Cheapies not recommended, goldplated fancy ones not worth the money) (digital ones sound great, until they let you down with a flat battery) Then experiment with pressures on your own bike & weight & style of riding. In order to get the best life out of your tyres, one have to accurately control the tyre pressure. It is much more sensitive to pressure than you can imagine. I once took a good 50% worn tyre to replacement in 500km of fast tarmac riding on 1.3bar. And only afterwards realised how lucky I was, not suffering a blow-out! The recent track day was a revelation to me, regarding the behaviour of the tyres. How they heat up and feel/handle early and late in as few as 3 laps. By the way, for the track riding they recommended 2.5 front and 1.8 back. I used 2.5 front and 2bar back. The tyre pressure is a compromise between Traction, Wear and Heat build-up. The pressures recommended by the manufacturer was established by them trying to offer the general user with an optimum balance between good wear vs good grip. You as intelligent rider should adjust the recommendation to suit your own detail needs. The softer tyre gives larger footprint ---- better grip on dirt, but greater heat build-up on tarmac (leading to quick wear). Harder tyre = smaller footprint, less grip on dirt, good grip on tar, reasonable heat build-up, reasonable wear

Nee man! Kry 'n meter, dan weet jy waar jy staan met die bande. Hoe weet jy of hard trap of sag trap. Grte :)

Thanks Danie for such a detailed reply. This helps a lot - along with the other opinions.

Aan Geelkameel, Dankie vir jou response ! Wat ek wel ook gevind het is dat 0.1 bar 'n verskil kan maak. Die toleransie (Fout) op die verkillende meters is waarskynlik meer as dit, dus vandaar my "boere plan". Ek stem saam, 'n betroubare meter is sekerlik die regte ding. My pen-tipe wat op die bakkie werk, registreer egter nie my Dakar se banddruk. Valve is sekerlik funny (of iets.) Sal gaan kyk na die by Midas ... Ek is nogal spyt ek kan julle nie join na Middelpos. Het drie trips met die baas(liefie) onderhandel tot einde van die jaar, nl.:1)Matroosberg GSC voorbereiding, my eerste GAGSC(kan nie wag hiervoor!), en die Weskus trip in November. Moet nou nie my geluk te ver probeer druk ... Groete

Regso! Iets wat ek ook gevind het is dat die meters by die petrolpompe dikwels verskil van my meter, soms tot 0.3bar. Daarom gebruik ek my eie meter om te check, sodat, al is my meter "uit"/nie perfek gekalibreer nie, ten minste is my banddruk elke keer dieselfde volgens my meter.

Hi Danie Like the detail but just to clarify. When you wrote "Wet weather - same pressures, reduce speed, increase awareness" did you mean 1.5bar F&B one up, 1.7bar two up F&B etc. I have always used the factory setting and find them Ok, but would be keen to try out your theory, particularly in the wet, as I ride through any weather. Now, does this apply to knobblies as well? Donald Own a GS and never run out of road.

By "same pressure" I mean hard (factory pressures) on wet tarmac, Soft (as for dry dirt) on wet dirt. Knobblies - I dont really know, presumably similar pressures. Same principles should apply.

I bought a mid price pressure gauge - rubbish. Take pressure readings of the same tire and get different values. Invest in a quality gauge - I whish I could tell you where to get this. Remember that all the vibrations on a bike is absolute murder to a gauge, so try to wrap it in bubble wrap (do get new wrap once you have popped all the bubbles). The problem I have with the RT is that the garage hoses does not fit on the valve. Their pipes are straight, I need something with a 90 degree angle. Any help?? Jaco, kyk na die pen tipe meter. Aan die binnekant van die punt is n meganisme wat die valve se pennetjie moet indruk, sodat die meter die band se lesing kan neem. Wanneer die valve te diep ingedraai is, kan die meganisme nie die pennetjie diep genoeg indruk nie. Normaalweg kan die meganisme gestel word deur dit te draai. Draai die meganisme op die meter n klein bietjie uit en kyk of dit help. Moenie die valve draai nie!!