Lowered bike bad MPG

[Joeyjoejnr 96]

Hello,

 

I need to get to the bottom of this.  Im fairly sure my front brake started rubbing since I lowered my 750X by 40mm. I noticed that on the trip computer I only got 241 km on a tank (well its flashing on the last bar) These would be mainly motorway miles. I bought and fitted new front pads and changed the brake fluid.  I also cleaned the pistons and re greased caliper parts.  The only thing I can think of now is when I lowered the rear by 40mm it put more of a kink into the front brake line causing the brakes to rub more than normal???

 

So if anyone else lowered their bike by 40mm, did you notice a difference in mpg or the front brake rub more than normal?

 

Im fairly sure the chain is set at the correct tension.

 

Its quite possible the bike is nearing the 16k service also.

 

Regards

Joe

[embee 7,288]

If you've lowered the rear 40mm the setting for the chain slack will be completely different.

 

The minimum slack point with the standard dogbones etc will be around 60mm of wheel travel. That is the measurement I made on the Integra, I guess it'll be pretty much the same for the S and probably not wildly different for the X. You've already taken up 2/3 of the travel to this minimum point, so the required slack setting when on the stand will probably be considerably less.

 

The only reliable way for you to decide this is to get the bike on a centre stand and disconnect the dogbones, then raise the wheel from the ground and find the point of minimum slack. Adjust the chain at this position to give minimal slack, say 10mm (as long as it's not actually tight and has some free movement so it is not loading the chain and bearings etc).

 

Then refit the dogbones and put it back on its wheels and see what slack you have, this will then be your setting value.

 

I don't think that will be the cause of poor fuel consumption, far more likely to be dragging brakes. Do they get hot when normal riding and not using the brakes? There's no reason why lowering the rear would make the front brake drag, if you've done significant work round the front caliper that'll be the place to start looking.

[Guest GBH]

We have a 40mm lowered 750SDCT and it returns between 70-108mpg depending on how you drive it. The shortened side stand and dog bones were fitted by the Honda dealer so I have no idea about the chain being adjusted, if it was it would only be a small amount and you would do it per the manual for a stock bike.

Sticking/binding breaks would have a drastic affect on mpg just check for heat after a few miles without touching the breaks if it's hot then strip and clean the calliper probably salt has got into the pots or slides.

[iaink 346]

I have lowered my X by 40mm and there is no difference to the MPG.

[Joeyjoejnr 96]

Ok thanks lads. A small update. As I pulled out of the drive way this afternoon the fuel gauge was showing 3 bars for about 1 mile then went back to empty. Doing 120kph I get an average of 4.1L per 100km. I wonder if my clocks/computer is acting up.

As for calipers I just realised there is one part I did not clean and grease. I forget the name of this. I think it's called the carrier. Its a metal bracket that connects to the caliper.

I will recheck the chain tension again.

[lazlo woodbine 1,211]

The only reliable way to check the MPG is to fill her and zero the trip meter. Ride and fill again. You have kilometers and liters and then do your calculations.

[trisaki 2,029]

When you cleaned the pistons did they push back easily , or were they quite firm, if that's the case you may find new seals are needed ( holding on too tightly to the pistons)

[Joeyjoejnr 96]

When you cleaned the pistons did they push back easily , or were they quite firm, if that's the case you may find new seals are needed ( holding on too tightly to the pistons)

After cleaning the pistons pushed back quite easily just using my fingers.

[trisaki 2,029]

Brakes sound fine , check the hose isn't kinked , pump the brake lever then try turning the wheel , should spin freely