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Discussion Starter #1 (Edited)
Because I'm not too familiar with wrenching on my bike I've always "trusted" the work to be done by a pro, until today...

Lots of talk lately on the forums regarding sloppy throttle response etc... even with Rays mod and Ivan's flash, my bike had terrible throttle response and was super sloppy. Shifts were never smooth and there was always a lag between the throttle twist and the motor actually coming to life. Again, with all the recent discussions regarding throttle response and play, I decided to look at it myself and see what I can learn. Looking in my manual and checking the throttle play numbers, I had waaaaaaaayyyyyyyyyyy more play than I should, probably 3x the suggested amount.

So I grabbed Rays instructions for the throttle mod grip install and headed to the garage. A minute or so later, my throttle was tight and the response was unbelievable. Checked full to the left and right and I was good. Let it run in neutral and blipped the throttle a few times with varying levels of "blipping" and still no issue and, it was much more responsive.

So after I adjusted it, my wife and I took off on a ride and man, it felt like a different bike. Gear changes were much smoother, the bike was more responsive and when I needed to roll of the throttle and back on it, it wasn't the sloppy nightmare I had before... Just like what Everybody had been describing with Rays mod that I hadn't been experiencing.

Now here's the most unexpected and interesting result. DISCLAIMER: remember, I'm not any kind of self proclaimed mechanic or expert so forgive me if this is normal.

After adjusting the throttle cable, my RPM's dropped. It used to be when my speedometer read 70mph I was running right at 3000rpm. After the adjustment, I was running 2800rpm with the speedometer reading 77mph. (also verified speeds with my gps as well) I checked lots of speed marks over a 160 mile ride and my rpm's were always lower. I actually got better fuel mileage than I had been getting too.

So, is that a freak accident or is that normal? Either way, what is causing the rpm drop? I like it, my bike runs more smoothly and I burn just a bit less fuel but, I'm really curious as to what's happening...

Anyone?
 

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With a standard transmission it is not possible for the relationship between speed and engine rpm in a given gear to change.

For example: If you previously drove at 70 mph in 5th gear at 3000, the RPM would not drop AFTER ADJUSTING YOUR THROTTLE FREEPLAY...the systems are unrelated. It would still require that your engine spin at 3000 RPM to achieve 70 mph in 5th gear. I would suggest that your tach is not reading 100% accurately/consistantly or that you simply misremember what rpm you were previously turning at a given speed or gear.

You might want to check out this link...it shows that on some bikes the tach can be in error by as much as 500 rpm:

http://www.superstreetbike.com/how-to/your-tachometer-truthful-mythbusters

The "power of suggestion" is an amazing thing. Now that you have removed the slop from your throttle freeplay the bike is now more responsive to your inputs, but that does not change basic mechanics or the laws of physics ;)
 

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Like Vulcan Hammer said, unless you change the gearing somewhere, rpms and speed will always be the same, I will include different tires can change this also. Its possible you are now running in 6th rather than 5th at these speeds. You mpg could be a result of not usng so much throttle now when speeding up because the response comes on sooner?
 

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Discussion Starter #4
Same gear, same speeds just better performance. Maybe the tach is reading just a bit off somehow. This is a road I take all the time to work and I'm always in 6th...

Didn't think it was tied together but I wasn't sure. Regardless, I don't really care about any of it except the better throttle response, that's so nice.
 

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I know this is going to sound dumb but... are you SURE you weren't in 5th gear before? Some folks have had issues with the shift indicator. Is it possible you were in 5th, but indicating 6th?

As the other poster pointed out; suggestion is REALLY powerful. Our brains can convince us of things that absolutely never happened based on our perceptions. During my undergrad I wrote a paper on the placebo effect and did a little digging into a couple of studies where participants actually physically broke out in hives, because they had been convinced (with hollywood makeup and actors) that they had been exposed to a rare and terrible virus. In fact, the researchers called the CDC thinking there actually HAD been a virus outbreak; and it was just a terrible coincidence connected to this study on the effect of mass hysteria. The power of suggestion is THAT powerful; so it can definitely convince us the RPM's used to be higher.
 

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It is a well documented phenomenon. They all run better after the laying on of the hands. It doesn't matter if it's a wrench or a rag.
 

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Discussion Starter #7
I know this is going to sound dumb but... are you SURE you weren't in 5th gear before? Some folks have had issues with the shift indicator. Is it possible you were in 5th, but indicating 6th?

As the other poster pointed out; suggestion is REALLY powerful. Our brains can convince us of things that absolutely never happened based on our perceptions. During my undergrad I wrote a paper on the placebo effect and did a little digging into a couple of studies where participants actually physically broke out in hives, because they had been convinced (with hollywood makeup and actors) that they had been exposed to a rare and terrible virus. In fact, the researchers called the CDC thinking there actually HAD been a virus outbreak; and it was just a terrible coincidence connected to this study on the effect of mass hysteria. The power of suggestion is THAT powerful; so it can definitely convince us the RPM's used to be higher.
Yes, I'm absolutely sure...
 

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The thing is, physics are physics. No computer adjustment or air/intake adjustment or throttle adjustment can change the RPM's in a given gear at a given speed. This is unlike an automatic transmission with a torque converter that has some 'slop' where RPM's can change at the same speed and gear depending on load, which can sort of be manipulated by computer. The only two options here are either that for some reason you weren't able to get it into 6th gear and it was indicating 6th while in 5th (5th gear at 70mph is around 3,000 RPM IIRC), or your clutch was slipping massively and should be repaired immediately. I suppose a third option could simply have been your tachometer being several hundred RPM's off (they are all inaccurate but generally accurate against themselves. i.e., generally, if the Vaquero's tach is 200 RPM's off, they are ALL 200RPM's off, so two bikes going side by side at the same speed in the same gear, unmodified, would show the same RPM)
 

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Perhaps the OP had a lot of clutch slippage which somehow was eliminated via some sort of adjustment - that's the only plausible manner in which the supposedly reduced rpms at the same road speed in the same gear can take place . . .? as noted by Romans 5:8.
 

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Given that it's a hydraulic clutch I can't imagine what that 'adjustment' would be; but I suppose it's possible! But given that OP saw the RPM's in sixth that are identical to what they'd see in 5th, I'm leaning towards some issue with the gear shifter; indicating 6th when it was in 5th and perhaps not letting him shift into 6th.

Now that I rack my brain for a moment on that; I almost wonder if the slop in the throttle was causing it to 'hang up' a bit. These transmissions will actually shift under load pretty well and it SHOULDN'T matter with the clutch pulled in, but if all the starts were a lined and everything was 'broken' at the same time, perhaps it wouldn't shift into 6th.

Any old Doctor will tell you medical school 101 is "When you hear hoofbeats, don't look for Zebras, look for horses". Sometimes the obvious stuff is the right stuff. In this case, if it's doing 5th gear RPM's in 6th, then it was probably actually in 5th.
 

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Discussion Starter #12
Given that it's a hydraulic clutch I can't imagine what that 'adjustment' would be; but I suppose it's possible! But given that OP saw the RPM's in sixth that are identical to what they'd see in 5th, I'm leaning towards some issue with the gear shifter; indicating 6th when it was in 5th and perhaps not letting him shift into 6th.

Now that I rack my brain for a moment on that; I almost wonder if the slop in the throttle was causing it to 'hang up' a bit. These transmissions will actually shift under load pretty well and it SHOULDN'T matter with the clutch pulled in, but if all the starts were a lined and everything was 'broken' at the same time, perhaps it wouldn't shift into 6th.

Any old Doctor will tell you medical school 101 is "When you hear hoofbeats, don't look for Zebras, look for horses". Sometimes the obvious stuff is the right stuff. In this case, if it's doing 5th gear RPM's in 6th, then it was probably actually in 5th.
Hydraulic clutches do have a little adjustability, I've had it done. My mechanic said there's a pin, or something like that, that will slightly adjust where the clutch actually begins to engage. For the longest time, even when brand new, my clutch lever had to be almost all the way let out for it to really grab. Asked the mechanic about it and he told me about the adjustment. It was adjusted and engaged sooner. Not a ton of difference but enough.

I will say this one last time, I am 1,000,000,000,000,000,000,000% positive I was getting into 6th gear. I don't use the gear indicator on the dash for anything more than confirmation. I count the shifts and if I feel like It's winding out more than normal, I'll almost ALWAYS pull the clutch and see if I can kick it into another gear. My daily work trip is 155 miles, round trip, on an interstate with a speed limit of 70mph, most do 80mph plus, so again, I spend most of the trip in 6th, not 5th thinking it's 6th, it's 6th gear. Again, I know this because I count the shifts....

I think I'm smart enough to discern what gear I'm in. I'm by no means a mechanic but, I'm fairly intelligent and I can do general mechanic work. I'm a very technical person by nature however, I don't have tons of experience with motorcycle systems.

Thanks everyone for your input. The "interesting result" really wasn't anything more than an attempt to gain more knowledge as to how my bike works. It works fine, rides fine and I don't mind if it did drop a few rpm's, again, I was just seeing if I could learn anything more about my Vaquero.
 
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