Hey all,
Now that I have had my bike for a bit now, there are a few things that are starting to bug me. Wondering if anyone can shed some light on this:
1) first is the fuel mileage. Doesn't seem very good. I reckon I get about 150 km or so to a tank (from 'full' til when I switch to RES). Usually about a 10-12L top up. That equates to 6-8L/100kms, or in the US of A, 29-39mpg. Seems a little low. I don't usually go above 8-9k rpm, trying to keep them below 6 usually. I am running a test currently on exactly how many km's I get on a tank. I do a fair amount of hwy riding, so I'd expect higher
2) I get this terrible "buzzing" or "rattle" from what sounds like the cluster area. I know its not the cam chain (already changed the CCT for an APE, and it buzz isn't rpm dependent). It's hard to get a video to accurately record the sound, as my camera on my phone is not the best. Warm or cold, it doesn't matter. It doesn't do it at idle, but when I spool up a bit, it buzz's. Any ideas?

TIA

 

I get approx 40-45 miles per gallon with a stage 1 jet kit and -1 front sprocket. That does seem a bit low. I noticed that when I adjusted my air/fuel screws on the carbs a bit too rich I lost a substantial amount of fuel economy so that might be worth looking into. Do you know if the jets & needles on your bike are stock or aftermarket? If someone put an aftermarket jet kit in there the needles might be clipped up higher than stock which would run rich & lose fuel economy also. It's probably carb related either way unless it's something like dragging brakes which I'm sure you would have noticed.

Does the buzz happen sitting still when revving the motor or while moving? I was thinking maybe something related to the speedo cable, but if it happens while sitting still that pretty much rules my theory out..

 

I reckon everything is stock. It still have the stock airbox and muffler, and the mains are 102's. The brass caps for the idle adjustment are still intact so unless they backed themselves out to richen the mixture. I have not yet inspected the plugs.

As for the buzz, it seems to be speed related. I don't think it does it when revving at a stand still. Maybe tach related? The speedo needle does bounce around >20-30 kph before it works smoothly.

Another thing to add to my list is the temp gauge seems to be not working well. When riding around, it usually sits right at cold, sometimes it will jump up to 1/3 or so then drop back down. The fan still kicks in when its hot out or in traffic.

 

Might try to lube the speedo cable and see if it helps the problem at all. I don't know that the cable would cause rattling noise, maybe it's the gauge itself, but I think if it were the tach it would happen even when standing still and revving the engine. Considering the speedo bounces around at low speed I would be inclined to look in that direction.. my speedo works smoothly at all speeds.

Seems that the carbs are mostly stock by your description, I just can't think of much else that would cause a large loss in fuel economy other than something like dragging brakes or a change in gearing. What is the elevation above sea level where you are?

 

The temp gauge issue sounds like probably a bad sensor, bad wiring, or a gauge problem. You can test the gauge by taking the single wire connected to the temp sensor by the t-stat, and attaching it to ground with the key on. The gauge should sweep quickly up to full hot.. just make sure to disconnect it before the gauge pegs all the way to avoid damage. If the gauge works as described it and the wiring are probably ok.

If you have a multimeter there is a chart in chapter 5-5 of the service manual that gives approximate resistance values vs temperature that you can use to check the operation of the sensor. My bet would be a bad sensor or corroded connection. If the fan is still turning on in traffic/hot weather the bike is reaching the correct temperature in the cooling system.

 

Ok, after going down and checking, I've confirmed it does it even just reving at a standstill. Not speedo related. I've tried to get a video, let see how this works...

As for my elevation, more or less sea level. My door is a 10 minute walk from the ocean

 

Wow that's definitely a pronounced rattle I can hear it clearly.. any idea where it's coming from location wise? I don't really have any good ideas to offer without hearing it in person to be honest, is there any way you might be able to isolate it to a general location? A long screwdriver can be used as a decent alternative to a mechanic's stethoscope.

From the video it sounds like something rattling externally vs an internal engine noise..

 

Its definitely coming from the cluster. Its kind of a pain in the *** to remove the front fairing, but maybe this week I'll give it a shot.

 

UPDATE: I did a run from Full to empty, 203km's (~120mi) before hitting reserve. 13L to fill, gave a rough mpg of 37-38 mpg. Not bad I guess...

Going to Vegas this weekend, than to Seahawks - Greenbay next week (GO PACK!) so I don't know when I'll find time to strip off the fairings. I am ordering a Delkevic slip on this week so maybe I'll just set aside a weekend to do all this work that is piling up!

 

That's pretty decent.. could possibly be a bit better, but at least there's no major issues going on if you can get close to 40 mpg. I would suggest doing every maintenance/tune up procedure in the manual that hasn't been done since you bought the bike and see if that helps it out any.

As far as the noise from the cluster you might try disconnecting the tach input to the cluster and see if the noise goes away.. I don't think it has anything to do with the speedometer since it does it sitting still & revving the engine.