To Screw or Not to Screw? By ducked (Read 764 times)

[ducked]

That is the basic scooter maintenance question.

I'm taking advantage of the GF being away in China to screw around with/hopefully fix her scooter, which has been pissing oil for ages. Anyway, I've never worked on a scooter before, so I did a bit of Googling.

Most of the web info is for US market GY6-engined Chinese imports, and there seems to be some disagreement over whether you screw the oil filler plug/dipstick in when checking oil level, or not, with the majority apparently favouring not.

absolutelyscooterparts.net/pdf/C ... manual.pdf

Says "The cap needs to be screwed in for proper reading" next to a picture of a filler plug/dipstick that looks exactly the same as the one on the Yamaha (a lousy design incidentally, provided with large un-cleanable grit traps, just what you want above your oil fill port. Not surprised Yamaha chose to copy that.)

The other manuals I have, all apparently based on the same GY6 document which probably comes from Honda, all say "Check the oil level when the oil dipstick is unscrewed and out", which is a bit vague/meaningless.

Presumably they mean the thread is just on the point of starting, but didn't care,( or couldn't figure out) how to say it, being Asian, and thus culturally hostile to clarity in writing.

www.chinesescooterreference.com/pdf/daw ... manual.pdf‎

The Scoot Dawg manual, written by Americans for Americans, also says "Do not
screw the dipstick in while checking the level." so that seems to be the way to bet.

Bit inconsistent, but nothing compared to the confusion surrounding published cylinder head torque settings.

[DrRocco]

Even though I am a screwing enthusiast, I do not screw in the dipstick while checking the oil though.

[Deleted]

Mar 14, 2014 6:42:57 GMT -6 DrRocco said:

Even though I am a screwing enthusiast, I do not screw in the dipstick while checking the oil though.

yeah you dont screw it in when you check oil.

[ducked]

Well, I've been screwing it in (and screwing it up) so I spose I've been under-filling a bit (and telling her to). Moot point though, since when I've checked she's usually running it about half empty.

[kz1000st]

Where is the oil leak? It could be as simple as a valve cover gasket or as complicated as a crankcase gasket. Any idea where it's coming from.

[Deleted]

KZ, heres his original thread: scooterdoc.proboards.com/thread/9513/yamaha-breeze-torque-specs-manual

[Bashan]

The Japanese bikes tend to say screw it in all the way oh baby. But the Chinese bikes, including CF Moto say do NOT screw the dipstick in. Consult your manual but I've been up and down the pike on this. Chinese, don't screw the dipstick down.

[ducked]

Thanks. I don't have a a manual for this particular machine, but the first 4 Yamaha owners manuals I checked in your library (VERY USEFUL RESOURCE, thanks a lot) all say no screwing, so that'd be the way to bet for this machine. (Yamaha Breeze 125 scooter)

Strange if Japanese and Chinese GY6 recommendations are different (its a Honda engine originally, yes?). Suggests it doesn't matter very much, unless the dipsticks are very different.   

[twowheeler]

As long as you have a working crankcase ventilation system or catch setup that little bit wont hurt anything.

[ducked]

Mar 17, 2014 5:09:59 GMT -6 twowheeler said:

As long as you have a working crankcase ventilation system or catch setup that little bit wont hurt anything.

That comment seems to assume overfilling.

Since I've been screwing...er.... apparently where I shouldn't , I've been underfilling. 

A bit.

I think.

I'd agree it won't matter though.

[Bashan]

Oddly, I just changed the oil on my SYM which is Taiwanese. The manual says do not screw the dipstick in. I did a little analysis and determined that since the dipstick is on a slant, the actual vertical difference in the level of the oil between dipstick in or out is around a 1/4 inch on this bike (300i). I will try to determine how much oil that actually represents but I doubt it is significant. Every source I have ever read says too much oil is worse than a little deficit. Unless your dipstick is vertical, if there's a doubt go with out. OMG, do we now have a Scooter Doc mnemonic device?

By the way, Chinese Scooter reference is my site, I built it. I was raw and some of the information is incorrect. Like any reference, keep that in mind, none of them are 100% correct. Chinese Scooter Reference has so many Google hits that redirect to Scooter Doc I can't just take it down. It's one of things you keep putting off. Rich.

[davec]

I have a Goldwing and a Shadow Sabre 1100. Both say to NOT screw it in all the way.
AND, to measure the oil with the bike on the center stand/level.
(My Sabre doesn't have a center stand, so I gotta momentarily hold the bike upright then back to the sidestand, then check the level)
BUT If not screwing it in and filling to half way between the NEED OIL mark and the FULL mark, then screwing it in ALL the way would assumably measure to the FULL mark.
Or, do a little experimenting and see where the oil level is when screwed in all the way, and not screwed in, and adding a little and see where it measures at.

I'm assuming that the oil level is gonna be the same screwed in or not screwed in, just indicated at different level on the dippy sticky.