Rear sprocket bolts Qingqi QM200GY-BA

[forchetto]

Thank you for your comments. Have you done a tour of the forum yet?. There are quite a few bits and pieces concerning our bikes here.

Also, I've just found out the reference number for an equivalent sprocket from JT Sprockets, reference nº JTR 809.44 . Put that reference in the buyers guide search box that appears and it goes straight to the right sprocket:

http://www.jtsprockets.com/61+M54a708de802.0.html

The Suzuki bolt only just fitted in the hub. Before you do the final fitting, run the screws into the holes to ensure they will fit without bottoming and no metal has to be removed to accomodate the plain shank section.

The dimensions of the drillings on the Qingqi's hub are as follows:

Overall depth of hole 32 mm
Depth not threaded 7 mm
Depth threaded 15-17 mm

If you find the bolts bottom out due to the unthreaded shank touching the start of the thread you may have to remove one or two of the first threads in the hub with an 8.2 or 8.3 mm drill. There's plenty of thread left.

Just for the record, did you manage to retrieve the broken bolt?. I'm curious to know where about its length it sheared. This might confirm our findings. Also have a look at the remaining bolts to see if there's any sign of strain somewhere along their lengths. What tends to happen is that the sprocket moves slightly and, due to tolerances, not all screws take up the shear strain equally. One of them will do that first and that will be the one to shear first followed by the next one that touches the side and so on.

[ianl1201]

I was able to retrieve what was left of the stud...it was pretty mangled but from what I could tell there was no shank left and it did look as though it might of broken at the top of the threaded section as you suspect.

I've just ordered the sprocket and bolts and hopefully it'll be a straight fit. Will let you know...did you have to remove some of the thread or did you get away with it?

I've had a good look round the site now and it's excellent - just the sort of resource I was looking for to get more info about my latest bike. I'm certainly enjoying the lower running costs of the RMR compared to my GSXR! I'm definitely a convert to the China Moto way of life!!

[forchetto]

I did some measuring of the holes with the depth probe of a vernier calliper, and mine was just right, but the holes differed slighly and so I tried the bolts on first before torquing up. Mine were just OK, but with tolerances, etc, other bikes might not be and require slight metal removal.

The weather is so crap here at the moment that I still haven't been out to test the new gearing...will report as soon as I can.

My fuel consumption is around 3.1 litres/100 km or something like 76 miles/US gallon, 91 Miles/ UK gallon. I'm not a fast rider though, others may not be as economical.

One important thing to consider with this and all other Suzuki or Suzuki-derived singles up to 250 cc, is to keep an eye on the oil level. The sump only holds about a litre, about the same as a Honda 50 Super Cub, and if the level drops only a bit, lubrication is compromised.
First thing that suffers are the camshaft bearings. Their plain bearings running straight on the cylinder head alloy will start to wear prematurely.

The oil change intervals in my handbook are at 4000 km. I believe this is far too long for such a small quantity and would recommend changing sooner. At about 2000 km. What do others think?.

[ianl1201]

Thanks for the words of advice about the oil Forchetto. I always tend to change the oil on my bikes more frequently than recommended. Worthwhile, especially if it's such a small amount.

You had a chance to try out the new sprocket gearing yet? Mine arrived today but won't get chance to fit it for a while. By the way, I can recommend Wemoto in the UK for suzuki spares....I ordered yesterday lunchtime and the sprocket arrived today! Great service.

[forchetto]

Haven't tried it yet. Hasn't stopped raining for weeks...At the moment I'm trying (without much success) to adapt a chain tensioner to mine before I take it out.

I'm surprised by the quick sprocket service, specially as this is from a fairly rare and old models. I got mine from a very large Dutch spares specialist:

http://www.cmsnl.com/search.php

But they took several weeks to supply. I'll make a note of Wemoto for the future.

[forchetto]

The sun finally came out today and I was able to have a decent ride on the Qingqi, now fitted with a 44-tooth wheel sprocket rather than the 48-tooth that came as standard.

I was worried that pulling away from standstill would involve a lot of clutch slipping with the higher overall gearing. This was not the case. The initial impression is that first gear is now useful. Before this, it was just a gear for pulling away and changing a microsecond later. Now it's a useful gear, even goes up to more than 30 kmh if you want to. Much better for slow city work where you were either screaming in first or bogging down in second.

Overall the bike feels more "long legged" and far more relaxed without noticeably losing any of the instant pulling power that a low geared box gives you. The torque spread of the engine means that you can still potter along country lanes in 5th at 2500 rpm if you want, without any transmission snatch, and now reach a top speed of around 125 kmh (Indicated). You can cruise at max torque at 7000 rpm with the speedo showing 115 mph leaving another 1000 rpm before the power peak at 8000rpm.
The rpm readings are at best approximate as the rev-counter has tiny, not very precise calibrations, and I can hardly read it without my bi-focals...it's the age you know! (mutter, grumble...).

I did a highway run against a rather strong head wind and in a slight up gradient the revs fell off to such an extent that I had to drop a gear to get back up to a reasonable speed. I don't think it would have been much different with the original gearing.

The vibration that sent my hands to sleep after a few miles is not there anymore. There's vibration, but not so noticeable now. This could be due to the gearing shifting the vibration period further up the speed scale as well as the silentblock vibration damper now fitted between the new P&P exhaust can and the chassis. I have found this to be efective on other vehicles too.

As an aside, I can't recommend the P&P exhaust can enough. Apart from the gorgeous sound it produces, it has perked up the mid range power no end. The removal of the catalyser built into the factory silencer is responsible for the extra power. The efficiency improvement of the new can was evident from the first start up: The idling speed increased and needed to be reduced straight away, proof of combustion efficiency. You often get this effect, without touching the carb settings, with the engine running, as you carry out such adjustments as the timing advance (on systems where you can do this), carburettor synchonisation on multi-cylinder machines, etc. The revs rise as the combustion improves using the same carb settings.

Link to can seller: http://xian.west-wire.co.uk/index.ph...d&productId=13

Details can be found on this thread: http://www.mychinamoto.com/forums/showthread.php?t=499

My PGO (Quadzilla in the US) mini-buggy rattled away merrily until I fitted a new can with a similar anti-vibration mounting. The difference was astonishing.

Have I mentioned the beautiful handling, suspension action and slick gearbox of this bike before?...it takes me 10 minutes to stop smiling after a ride on our mountain roads.

[ianl1201]

Hello Forchetto,

Thanks for the excellent write up...I'm itching to get back out on my RMR again now! The weather actually improved enough at the weekend here in the UK to let me do some spannering on my bike, but there's still too much salt on the roads to take it out yet...I'd watch it disintegrate in front of my eyes judging by the damage a couple of trips in December did!! Perhaps corrosion prevention is the next goal for the Chinese manufacturers (although the japanese bike firms still have some way to go yet!). A thorough clean up has been carried out over the dark winter months and any removed bolts had a generous blob of copper grease before refit.

Anyway,managed to get my swing arm painted and refitted following the repair, my new sprocket is on and also the P&P can that I bought last month (these seem to be standard mods for 200GY owners eh!!) All I need to do is take a couple of links out of the chain (this weekend weather permitting) and I'll be all set for spring.

How many links did you remove from your chain by the way?

Thanks for the links...here's a couple for the parts I ordered - my sprocket was from www.wemoto.com - excellent service, and I ordered M8x30 bolts from www.stagonset.co.uk - again, quick delivery and they were 34pence each as opposed to 1.50 Euros each for the Suzuki items! Hope this is useful.

[forchetto]

I removed 1 and 1/2 links, three rollers. This got the chain back up to the beginning of the adjustment range.

Interesting about the bolts. Our local specialist supplier of hardware swore they didn't exist with that overall length and that unthreaded shank...gits. Mind you I can't find that combination in that fasteners page either.

I did pay 1.50 each to Suzuki. For that price I expected them to be made of titanium or myrrh...

The fasteners page is fantastic, by the way. Really well laid out and informative.

About the corrosion, one of the few defects I find on this bike is the frame paintwork. It's really thin all over and hardly has any gloss.

Keep the roller bearings and linkages of the (rather complicated) rear suspension well greased. They're very exposed to road crud, but they look well made.

[fenouilledes]

Hi Forchetto, Ian,
Thanks for the valuable info on drive sprockets, links and exhaust cans. I am a Brit living in France and ride a GY200 around the French Pyrenees. I too plan on changing the rear sprocket for reasons already mentioned in this forum.
I thought I would join this discussion as my bike seems to have a different rear wheel hub. The bike is from Shandon Pioneer (supplier of Pulse brand in the uk) and is factory supplied with 15/51 tooth sprockets. The rear sprocket is held in place by four studs/nuts instead of the six you describe.
I haven't yet stripped down the rear wheel but will investigate this further and share the information here.
Just wanted to say hi and à bientot !

[forchetto]

Welcome to the forum.

It's very strange this, Jinan Qingqi and Shandong Pioneer appear to be two different companies and yet they're in the same province: JINAN, and they make virtually the same bikes. On top of that Shandong Pioneer on their website : http://www.xfmotor.com.cn/en/ claim the same history as Qingqi, started in 1956, link with Suzuki technology, blah, blah, blah...Perhaps Crazy Carl or someone else that's lived in China can explain the relationship between those two companies.

You might find the reason for the sprocket teeth discrepancy is because your bike has a 520 size chain rather than my Qingqis 428 size. Check this by measuring the pitch, it should be 5/8" between pins or rollers and 1/4" wide rollers, if it's a 520 size.

The 428 size will be 1/2" pitch and the roller width is 5/16".

The rear hub differences are interesting, take a photo of it if you can. My bike has the sprocket held by six bolts with locking tab washers.