2015 Honda CB300F, Honda GN4 10W-30, 1000 miles

[pjs7]

Blackstone analysis of my brother's Honda CB300F.

Bought new with 10 miles. Previous oil changes done at 600 miles and 4000 miles, all with GN4. Maintenance interval from Honda is 8k miles.

Crankshaft recall was performed at 4000 miles after which the bike exhibited audible rod knock at idle. I own a similar bike, 2011 CBR 250R, that makes no such noises. The 300 bike was also smooth prior to the recall work.

Blackstone did not point out anything unusual and no metallic flakes were visible in this oil used from 5k to 6k miles. It performed well otherwise but has since been traded in on a Triumph to avoid any future problems with this bike.

 

[jeff78]

The picture's a bit small, but is the viscosity 7.60? If that isn't one of Blackstone's fuel dilution goofs, it means that little engine sheared the 10W-30 down to barely a 20 in 1000 miles.

 

[kschachn]

As you mention it is most likely fuel dilution not shear, despite Blackstone's fuel number. And from what I've seen on here their viscosity measurements also leave a lot to be desired.

 

[Artem]

Wait but if the engine was making weird noises post warranty work, why not just take it back in and have it repaired? Why dump a perfectly good bike?

Seems to me the next potential buyer will buy it and won't know what hit him when a rod flies thru the block. This could be prevented.

 

[dole]

rod knocking sound exists on my new Honda PCX scooter, I reckon it is a commoner.

 

[pjs7]

Sorry about the image quality. Viscosity was actually 7.00 cSt. Who knows when it comes to fuel dilution. They reported "trace" and a flashpoint of 375 deg F. There was probably some even though the bike was usually warmed up well.

Honda dealer that did the work denied there was any noise and wanted paid to do any further work. Its well out of warranty. The replacement was for a recall. When asked to value the bike for a trade in, they refused to provide a number since the bike "has rod knock" that they could now hear. The Triumph dealer didn't care since my brother bought a new bike. It's on them now. Still in their used inventory several months later.

Haven't heard lower end noise from any other little Hondas. I have a 250 and a Grom, uncle has a PCX, and father has a Metropolitan. Ive also ridden several Rebels. All are very smooth and quiet.