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Does a TB cross-over tube help surging problem?



Well, I am still contemplating the addition of a resistor to the TPS
circuit. My thanks are due Andrew for references.

True, various variables are considered by the ECU as Wayne has sounding
pointed out (well, not quite enough variables many would say). But the TPS
is the key determinant of injector duration, I'd guess. Much guessing when
it comes to secretive Bosch FI practices.

The general wisdom for non-invasive approaches to surge reduction is to have
punctilious tuning and synching. That's TPS zero=3.95 and butterfly and
bypass synching (using dual-vacuum gauges or ride-around 9v TwinMaxs).

Now with carbs, makes sense to me to have the largest feasible cross-over
pipe between the carbs as that helps average the two, correcting what
synching fails to do. Some wise people do not share this view, but you can
see the tubes on a lot of Japanese bikes with closely adjacent carbs, and my
previous machines. The flow capacity of even a 1/8 inch pipe to influence
balance is commensurate with the butterfly opening at idle and beyond into
the rather small openings used for surge-ridden highway cruising.

So, has anybody tried joining by tubing the test ports on the TBs?

Cheers.

Ben
- -- 
Ben Barkow, Toronto... 39 seasons on Beemers, 44 as a biker,
1961 R69s, 1967-1999... really sup'ed up and fast
1984 R80RT/rod, 1998- 5 extra peak ponies in a wider flatter power band,
  much modified 2-into-1 exhaust, CR 9.5, Keihin PJ 34mm oval carbs,
  dual-rate springs with cartridge emulators, BT45/S11, Saeng fairing
1999 R1100S, 2004- Leo Vince exh, JetHot coatings, Ben's windscreen

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