Qingqi QM200GY / Qlink XF200 alternative sprockets

[nedlin]

so is it right the less teeth on rear the better top end speed?

Maybe. I changed my rear sprocket to one with 4 less teeth and can go 55mph at lower revs; makes for more comfortable ride.

[CrazyCarl]

so is it right the less teeth on rear the better top end speed?

It's the same as gears on a bicycle. Smaller gear in the back OR larger gear in the front will mean lower revs at any given speed. Your bike and current setup will dicate what's the best route to go. Most common is, of course, changing the rear sprocket/gear. Sometimes the front one is easier though so it really depends.

CC

[CrazyCarl]

Maybe. I changed my rear sprocket to one with 4 less teeth and can go 55mph at lower revs; makes for more comfortable ride.

What are you riding Nedlin?

CC

[nedlin]

What are you riding Nedlin?

CC

'08 XF200SM

[nedlin]

Although I won't be "riding" the Qlink until next spring. It's about 15 degrees here in Michigan and the bike is in Maine. Thanks Carl for this forum; lots of good talk and info.

[david3921]

Where are you in Michigan nedlin? I'm in the Grand Rapids area. I have the XF200 also.

[nedlin]

We are visiting in A2 for a week or so. I noticed an '85 Honda Nighhawk for sale near you on craigslist.

[Sprocket]

My bike comes with 134 links of 428 chain and sprockets 15 / 48 tooth.

These bikes can benefit from a raised overall gear ratio to lower rpm's at reasonable highway cruising speeds, 44 tooth for the rear sprocket seems to be a preferred size to achieve this.

If we could get a larger 16 tooth engine sprocket it would be about the same gear ratio change and would reduce the amount of chain wear. The smaller the front sprocket the greater the wear rate. In transmission engineering circles it's reckoned that if your application requires a long life, conventional wisdom says don't use a small sprocket with less than 18 teeth. However, I have seen karts with 10 or even 9 teeth on the small sprocket. Most of these guys have to put new sprockets on every race...

We can't get these 16 tooth sprockets easily, and the housing design won't allow for a greater size to be fitted, so it's the rear sprocket for us:

Here are some alternative sprockets from a Suzuki TS125ER that will fit. The part numbers given are the original (OEM) Suzuki numbers, so we can walk in a Suzuki dealership and ask for the correct item without suffering the shame and embarrasment of saying we have a Chinese bike

64511-48730----428 chain----42 teeth
64511-48700----428 chain----44 teeth
64511-48720----428 chain----45 teeth

If you have a spare half hour, this is a wonderful site dealing with bike transmission issues:
http://faq.f650.com/FAQs/SprocketsOtherSizesFAQ.htm

In fact the whole site, dealing mainly with BMW's F650 is a powerhouse of knowledge and wisdom. Very extensive though.
http://faq.f650.com/main.html

Searching Ebay, it appears there is a 16 tooth sprocket available for the 428 pitch chain, it is offered as a replacement part for the Sinnis Apache QM 125 GY

428-16T

[nedlin]

Thanks Sprocket; lots of good detailed info on rpm/mph ratios with different sprocket setups.

[Sprocket]

Thanks Sprocket; lots of good detailed info on rpm/mph ratios with different sprocket setups.

Thankyou for saying thank you, but it is misaimed, for it was Forchetto who supplied the links to the websites where you found the ratios useful.

I have since found out in addition to the 16t sprocket on ebay, the distributor Tor Moto (uk) are also telling me they also supply a 16t sprocket which will fit the GY machines.

http://www.tormoto.co.uk/index.html