So it begins. Rider Magazine with First Ride report on 2018 Goldwing

dduelin

Tune my heart to sing Thy grace
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The first ride report in new Rider is long on technical details of the new GW with some new pictures of components but the ride portion itself is short. Honda did not release the bike outside of a controlled setting (Twin Ring Motegi race track venue) but the author and reportedly other invited journalists were quite impressed with their short rides of a few laps around the Motegi track. Honda not doubt ensured each invitee left with a large press release stuffed with many new details that we will see in print and digitally over the next couple of months until the bikes are in dealers in February 2018. I expect ride reports shortly on digital outlets from well known motojournalists similar to those in the three months preceeding the Africa Twin release.
 

ST Gui

240Robert
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I'm looking forward to ride reviews both short and long (rides and reviews).
 
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I haven't yet had a chance to read the entire article, but I did notice a couple of interesting things about the new engine design. It has a "Unicam" SOHC valve train with 4 valves per cylinder, and a single 50mm downdraft throttle body. I've always wondered why our ST1300s have 4 throttle bodies. A friend tried to explain it to me once, but I didn't get it.
 
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I I've always wondered why our ST1300s have 4 throttle bodies. A friend tried to explain it to me once, but I didn't get it.
Might have something to do with tuning the intake's air flow. Since each cylinder sucks air in only on the intake stroke, the air column is constantly starting and stopping, setting up pressure waves. If said pulses can be timed to yield positive pressure at the intake valve when it opens (or slightly thereafter) you will get more air in the cylinder for combustion and more power. This is just speculation on my part, I'm no expert.
 
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Multiple throttle bodies afford a combination of increased performance and better throttle control- the latter being less of a concern on a car versus a motorcycle.

Another point is that motorcycles, having so little rubber on the road as compared with cars, need utmost accuracy in torque control to apply power in corners. Four throttle butterflies close to the cylinders do a good job in this respect.

Why Multiple Throttle Bodies?
I think I've posted this response once before in a different thread. Kevin Cameron states in the above referenced article:
"Something on the order of a 10 percent torque boost can be had over a modest range of rpm by choosing the correct intake length. While pipes of this correct length could all be fed from a single “log manifold,” it has always been quite difficult to get fuel added at a single point to proportion itself equally among the four cylinders at all rpm and throttle angles."

Whether intentional or not, what he's describing here is what GM referred to as Throttle Body Injection (TBI) that was used back in the 1980's, maybe into the early 90"s. While this system was an improvement over carburetors in terms of cold starts (eliminated the choke butterfly) cold engine driveability and throttle response, aggressive corning without one of the cylinder banks suffering from fuel starvation, etc, it didn't hold a candle to port injection (MPFI, sequential port fuel injection, or whatever you want to call it). TBI still had some of the shortcomings as carburetors such as fuel pooling in the intake manifold, among other things. As far as I know, TBI has long been obsolete, although hot rodders can buy aftermarket TBI systems to replace the 4BBL carburetors on their upgraded 60's and 70's muscle cars.

So, much of what Kevin stated in the quoted text above doesn't hold water. While some advantage can be had by using multiple throttle bodies, what happens downstream from the throttle body or bodies is what matters the most, as far as I'm concerned. What I might consider a modest advantage in performance for moderate-paced riders such as me and likely a large percentage of forum members here would be a significant advantage to most road racers and riders who like to take their street bikes to track days on occassion, as well as dedicated "canyon carvers".

That's the way I see it.

EDIT: I did a little research after posting this reply and discovered BMW doesn't buy Kevin Cameron's theory on throttle bodies either. The K1600GTL has a single 50mm throttle body. For those who subscribe to the "more is better" line of thinking in terms of performance, remember that there is no substitute for cc's.
 
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I don't know why BMW opted to use a single TB as opposed to six, but any problem with throttle response may have been largely alleviated by using a servo controlled throttle, aka ride by wire system. I think this would be perfect for the ST1300, and that would make cruise control a no-brainer, but obviously the ST13 won't get any upgrades since it is not in production any more. No problem for me, if it was still in production the K1600 would likely be a better choice and likely in the same price range, and lighter than the new GL1800.
 
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