Effects of Altitude - 1150 GS

[waterloo]

In August my wife and I will be riding our 1150 GS to Tibet, passing through the Pamirs and Western Tibet. We will clearly be at a high altitude for at least one month, crossing 17 passes over 4500 meters in Tibet alone.
Three questions;

1. Has anyone had problems with this bike at altitude?

2. Has anyone had problems with poor fuel in this bike?

3. The bike is a 2003 1150 GS Adventure and has done 32,000 miles, has anyone had clutch problems with a bike of this age/milage?

Any help much appreciated.

Nick

[MikeS]

I have a 2001 GS1150 (non adv) with 76,000miles and having just ridden the length of south america, I´d offer the following;

1. Has anyone had problems with this bike at altitude?
Nope, highest pass was about 5000m.

2. Has anyone had problems with poor fuel in this bike?
Nope, regularly used 84 octane in Bolivia and didn´t notice any problems.

3. The bike is a 2003 1150 GS Adventure and has done 32,000 miles, has anyone had clutch problems with a bike of this age/milage?
Mine sometimes gives a false neutral but nothing serious so far.

Hope that helps

cheers

[Frank Warner]

1) The EFI system senses altitude and compensates for it. Even on the old 2 valve 2 K series motronic it was sensed and compensated for.

2) Only the newer 12s have knock sensors that can correct for engine pinging - the effect of poor fuel. If you get it - apply less throttle at low engine speeds, keep the engine revs up (use a lower gear) and all should be well.

3) regualrly replaced the clutch at 80,000 km intervals on my R80G/s .. that looks to be about its life with me at the controls. That would be about 50,000 miles. Errr about 50% dirt .. some of it hard travel.

[Chris_York]

R1100 GS Bolivia 4000+ m
easy on throttle low alt. bad gas, no prob. high alt.
climb tight switchback heavily loaded one person hard on clutch(smells like overworked brakes). 190,000 km original clutch

[Deke in AK]

BMW removed the requirement to lube the clutch splines when the oilheads came out. That said, there are quite a few bikes with problems from not lubing the clutch splines. It might be cheap insurance to pull the transmission and lube the splines before a trip of this sort.

Look here http://www.advrider.com/forums/showthread.php?t=207014

Cheers, Dennis

[Margus]

Altitude - no problem with Motoronic equipped BMW bikes.

I also agree on lubing the splines before the big trip. It's not just the clutch, the same also applies on the shaft splines on both ends that take all the power from the engine. Use high quality (molybdene?) grease, it'll last longer and works better.

Also paralever bearings (from the swingarm-gearbox casing side) need a good cleaning and greasing because they aren't closed bearings.

I do all the greasing every 50kkms at least depending how much dirt I ride. Dirt is keen to penetrate the paralever bearings in a long term dirt riding.

Optional insurance for VERY long trips is also replacing front wheel bearings, they cost very little.

Good advice is to take final drive main bearing + main (outer) seal + few different size spacing shims with you. They take very little room (compared with the chain+sprocket set for example) and cost very little (around 100$). You even can replace the final drive bearing on the road using hot exhaust to remove the old bearing and then i.e. submerge the housing into cold river water on mounting the new bearing IF the weather is too hot shomehow that the bearing doesn't mount on Usually heating the new bearing with a hot exhaust is enough (use gloves!) to mount it. Shearch in the UKGSer.com or ADVrider, there should be a pictorial thread how to do it.

Happy travels, Margus

[Warthog]

We were also in South America. Altitude was never a problem. We passed from Argentina in to Chile at over 3500m and it was fine.

My bike did appear to suffer from what a lot of people said was pinking (despite running on what was locally sold as 98-100 octane) and indeed changing down a gear and not opening the bike up in high gear avoided this.

We were two-up and had a lot of luggage, so the poor bike was working hard!

Having said that I never experienced a loss of power when the "pinking" was audible, which I would expect given what is actually happening when pinking occurs. Having said that it has not misbehaved in the slightest since we got back to European fuel. My only advice is that you will know when you get there if this is something that you will need to watch out for.

I seem to have had the problem on 98 or 100 octane, whilst MikeS above did not on crappy low octane....

Just be aware of it and act as advised if it occurs and all will be fine.

[oldbmw]

Do not worry at all about your bike at altitude. Enfields regulary make trips to high altitude without problems. As has been said both the cv carbs and motronic systems are largely self compensating. If you experience pinking it will be to poor fuel, because at high altitudes the cylinders will be running at a slighly reduced pressure so lessening the likelyhood of pinking. Stay warm.

[FatChance]

To be complete, at altitude, the bike will run fine (i.e. the air/fuel mixture will be metered properly so it does not run too rich), but the engine will not produce as much power due to the lower effective compression ratio because of lower air density. There just isn't as much oxygen to burn up there! Since your effective compression ratio is lower, your fuel's octane requirements will be lower as well. I live in the Colorado Rockies and at these altitudes, all naturally aspirated engines will be down about 10-15% from their normal sea-level power levels. When you get up to the 4-5000m altitudes, you will be down even more, though the engine will be still running properly and efficently. Nothing, short of a turbo or supercharger, will change that.

[MartijnP]

Hi,

I have had some experience with a 1100GS. Above 5,1 km. it started to have trouble. I could only go on in 1st gear, high revs. At 5,0 km. there was no problem whatsoever. This repeated when I went to 5,4 km. but the bike made it, although not comfortably. It seems there is a limit. Maybe the 1150 is different, by the way.

I rode at 76 Octane for days through sand in the Gobi desert, I felt no change in power at any moment..

Hope this helps,

Martijn