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Old 03-09-2012, 03:03 AM   #147 (permalink)
alvaro84
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Join Date: Jul 2010
Location: Fehérvárcsurgó, Hungary
Posts: 384

Teresa - '04 BMW F650CS
Motorcycle
90 day: 80.53 mpg (US)

The YARDIS - '99 Toyota Yaris 1.0
90 day: 59.52 mpg (US)
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Quote:
Originally Posted by low&slow View Post
For the uphill scenario you describe I would maintain my throttle position and bleed off speed as I climbed to the top , even if I had had to downshift , with just enough speed to be safe for the traffic conditions and then let the potential energy of going downhill accelerate me back to either my target speed or let me take advantage of an extended opportunity to coast in neutral. I hope this helps.
best wishes, L&S
On the hills I usually hold a speed that the actual gear can handle (so I don't downshift), pulse at the top and coast downhill. Most hills around here can't compensate for the aero drag at the speeds I prefer outside town (70-80km/h where the speed limit is 90 and the traffic sparse), so coasting there is more than safe. If the decline is long enough I even stop the engine, on a bike you won't lose steering not the brakes, so it's still pretty safe (just keep an eye on your mirrors!).

There are a few places where I DWL uphills, though. The best example in our vicinity is road 81 which is a busy road so I often stick to the speed limit (90km/h), except the place where there's a 60km/h speed limit around the crest of a hill. There I DWL down from 90 to 65-70 (which is the bottom of 5th on Teresa), and I may even downshift and go down to 60 (yes, I speed when I dont ).

Now if you use a Canon APS-C camera you're an expert at multiplying/dividing by 1.6, you know the mph values on sight If not, I'm sorry, this post would be a mess if I used 2 measurement systems in parallel

And the places where I'm in trouble: open roads with steep downhill stages, especially those of varying steepness. Engine brake is mostly too strong to hold a steady speed down, but if I coast, I accelerate to a speed too high for the bends. I'm in a pinch then: I either FAS and wear the friction brakes, or use the engine brake and go to coast time to time, while using gas to idle and brake - I can't fint the optimal way.

On using gas to engine brake: I have a technique to force Teresa into DFCO (just use the kill switch to stop fuel injection when the tranny is engaged and switch it on again in the same moment you grip the clutch to go coast - should work on any EFI bike, I suppose) but it's complicated and feels a bit like abusing her - after an extended period of forced DFCO she likes to stall when I coast. It seems the firmware can't handle my methods

Last edited by alvaro84; 03-09-2012 at 04:02 AM..
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