1988 PD06 Transalp carb jetting for altitude?

[chris]

Hi guys
This summer I’m riding my 88 Trannie in Central Asia. In places like Tajikistan/ Kyrgyzstan I could be up at 4000m/16000 feet above sea level. Has anyone ridden at altitude and adjusted/changed their carb jets? Currently the bike has standard jetting as it came out of the factory. Would you replace the jets? If so, to which size?

Many thanks for any advice.


Best wishes,
Chris

[ta-rider]

Hi Man,

I have just been riding a 125ccm bike up to 4800 meters altitude in Bolivia. There the engine lost a lot of power so i could onely ride up to 30 km/h insted of 100 but the Transalp is much stronger and for a "short" distance i would not start fideling around with the carborator. It also needs adajustmend afterwards scince the transalp has two cylinders. Just take it slower there and enjoy the landscape. I met people on a Africatwin and they told me they did not feel the difference

The maximum i would do is screw the german "Leerlaufgemischregulierschraube" kompletly in. Normal its 2.5 windings out...this helps if you ride at low rpm.

Reparaturanleitung und Wartung Motorrad Honda XL 600V 650V 700V Transalp PD06 PD10 RD10 RD13

Greetings, Tobi

[chris]

Hi Tobi
Many thanks for your very useful input. The bike has a huge 30 litre Africa Queens tank, so I need to have a look how I can access the idle screw with the tank in situ.
Chris

[ta-rider]

Hi man,

There are two screws one for each cylinder. Do you have a petrol pump as well? Otherwise you cant use the last few liters of petrol because the presure is to low and you carry wait for nothing.

Travel save, Tobi

[chris]

Yes, I have a petrol pump. And it works.... I ran out of gas the other day as the plastic reserve tubes had become detached from the fuel taps and were rattling around the inside of the tank. Previous to last filling up I had taken the tank off and had it upside down to repair a hole. They must have falled out.

Luckily I was 1 km away from a gas station and I could roll down the hill all the way to it.

Chris

[dstehouwer]

we just were in Bolivia with two africa twins without changing jets, and reached 4930 meters altitude.
Above 4500m, one bike ran on one cylinder :-S. The other was fine.
Sure, lack of power and huge lack of torque at low RPM's, but I wouldn't swap jets if I would have to do it again. On these bikes, it is such a nightmare to swam them...

[chris]

Originally Posted by dstehouwer

we just were in Bolivia with two africa twins without changing jets, and reached 4930 meters altitude.
Above 4500m, one bike ran on one cylinder :-S. The other was fine.
Sure, lack of power and huge lack of torque at low RPM's, but I wouldn't swap jets if I would have to do it again. On these bikes, it is such a nightmare to swam them...

Many thanks for the useful input. Yeh, I think I'm going to leave the carbs alone. Messing with them is a huge pain in the butt. When I rode my airhead BM a decade ago in South America with bing carbs next to my feet it was easy. But not on the Honda v-twins.

cheers
Chris

[beat_]

but is the fuel quality not a lot lower there?
so when the quality is lower, you need more (make it richer)
when going up in altitude it becomes richer
...
so do you actually need to changes the jetting?

just a thought..it's not my cup of tee.