The outside of a motorbike engine seen up close near the exhaust

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Keeway Front Sprocket

Blog Date - 25 September 2014

The gf's Keeway RKS 125 already has over 9,000 miles on it. Therefore that wear means a new chain and possibly sprocket are in order. The local Keeway supplier can supply these items, but they sure know how to charge! £50 for a standard, common or garden 428 chain that is "good enough for a 125", £33 for the rear sprocket and finally a further £16 for the front sprocket.

the front sprocket and the locking washer or tab on the keeway RKS 125
The chain and sprocket in question - note the locking tab/washer.

Sourcing a chain was no problem. Like many many other 125's the Keeway uses a bog standard "428" chain. I counted the links on the worn chain and found it had 116. I counted them again. And again. And again. Yep, definitely 116 links, I think. A brief search on fleabay brought up a DID heavy duty for £19 including postage. This is a well known and trusted brand name and I'm sure it will be far better quality than the "good enough for a 125" no-name expensive shop rubbish 

We decided the rear sprocket was barely worn but the front sprocket may need doing sooner or later. This is where it got a little complicated. The engine in the RKS like several other Keeways is marked up "KW157FMI". This is quite important because most of the Suzuki style engines in Chinese motorcycles are marked "K157FMI", the extra "W" is missing. The external difference is quite obvious, they look like the same motor to all intent and purpose except the Keeway's engines have more angular cases. I guessed that the extra "W" is there to identify the different cases.

the engine number on the keeway showing the "KW157FMI" engine type
There's an extra "W" in there compared to all the other Chinese bikes...

I took a long look at the front sprocket on the gf's motorcycle and the after-market sprockets for generic Chinese motors looked the same. At £8 compared to £16 from the dealer it seemed to be worth a punt, I ordered one. When it arrived and I removed the one off the RKS the difference became obvious, and I really ought to have spotted it. The Keeway has a recess into which the locking washer/tab sits. Without this recess the generic Chinese sprocket does fit on the splines but the locking washer/tab just...only JUST doesn't reach the splines. You could leave the locking washer/tab off, but this is VERY dangerous, there's nothing to hold the sprocket nut in place if it comes loose. 

Genuine keeway with cut out and the generic sprocket without it's cut out
The genuine Keeway sprocket is on the left, you can see the obvious difference.

As such we decided the safest sensible thing to do is get the right sprocket. It means we've wasted £8 on an unsuitable sprocket and we've paid £16 for a genuine one, but it's a small cost against what could happen if it all comes asunder. 

The next thing to do is work out if we can find a generic rear sprocket. The gf's rear tyre is fairly well worn and will be replaced in the not too distant future. When the back wheel is off I shall take some pictures and some measurements and see if there's something else that fits. Otherwise it's £33 for a genuine Keeway one. I'll let you know my findings...

Reader's Comments

Doug said :-
No chance of having someone pop it on a lathe and make the indentation for you?
1/1//2000 UTC
Ren - The Ed said :-
Doug, you know's defo a possibility! The keen eyed among you will notice the pattern JT sprocket is in fact 14 tooth as opposed to the 13 tooth original. The gf wanted to see what difference this made.

I am lucky, I have a friend at the bike club who is an engineer and I'm certain he'd be able to "turn" the recess, indentation for us. I also work at a company with several lathes and operators who would scoff at how easy this would be.

I think we might just give it a shot, just so the gf can see what happens to the bike with the different gearing.

Cheers Doug!
1/1//2000 UTC
Daf said :-
If you do get the sprocket fettled down, let us know what difference the extra tooth makes to the speed/acceleration!
1/1//2000 UTC
Joe said :-
front sprocket

rear sprocket
8/6//2016 11:39:42 AM UTC
Ren - The Ed said :-
Joe - you sir are a genius! I've looked all over the internet for the front sprocket and there you are - just handing it to me on a plate. Big thank you!

We have discovered the rear sprocket is the same as the GS125 - I'll add a link below to the details.

That's fab and it's half the price of one from the dealer.
8/6//2016 2:23:28 PM UTC
Danny D said :-
My bike is RKV125, is it the same sproket?
18/1//2017 7:27:43 PM UTC
Sharon said :-
Hi Danny D,

As I only have the RKS then I do not know if your Keeway RKV has the same sprocket as mine. However click on the link below and you will be able to find the right sprockets for your bike. These guys are cheaper than main dealers too. Hope this helps.
18/1//2017 11:50:38 PM UTC
franco paglionico said :-
can you tell me if keeway 125 wheels front and back fit a rmr 125 super byke
13/2//2017 10:24:00 AM UTC
Khalid said :-
I had this problem from about 2 years and the locking nut is came out and fall during riding and I made a new one by a lathe
14/8//2017 6:00:05 AM UTC
Ren - The Ed said :-
Cheers Khalid. Yeah a lathe is the way to do it...all I need now is a lathe.
14/8//2017 3:02:02 PM UTC
Ian Soady said :-
I've been telling you that for 2 years. Just think how much money you could have saved / how happy/sad (delete as appropriate) you could have made Sharon / how much time you could have whiles away instead of riding around on those noisy smelly motorbikes.
14/8//2017 3:11:33 PM UTC
Ren - The Ed said :-
So Ian, you're suggesting the route to my happiness is through a lathe? I think you may be right. All this motorcycling is hard work and I keep on wearing things out. Instead I should but an already worn out motorcycle and use my lathe to make it all nice again. Once it's all nice I can then admire it and ride it only if the weather is nice and only for a short trip. I can then sell it and repeat the process.

Oh hang on...this sounds familiar...?
14/8//2017 3:54:12 PM UTC
said :-
Hi. I´m Diego from Spain from

We can suggest as an option to the front sprocket, the ESJOT 15055.

You can take a look to it here-->

16/8//2017 9:39:03 AM UTC
Kieron said :-
Hi everyone i have a keeway tx 125 and im having trounle finding a front and rear sprocket set for it... can anyone help! Alls i know is that the back sprocket is a 50 tooth n the front is 13 teetg
18/10//2017 2:48:58 PM UTC
Ren - The Ed said :-
The UK Importers are MotoGB based near Chorley. I'd try contacting there and they ought to be able to steer you to your local dealer or maybe supply it directly to you. I'll add a link to their website.
19/10//2017 9:44:04 AM UTC
Ryan said :-
Hey guys, I know its been a while since anyone has posted here but I need help, I have just bought a Keeway RKS 125 2016 model and am starting to regret it. It seriously needs new chain and sprockets, both sides, the only thing I have actually found is a rear sprocket from evilbay. Any idea where I can grab these parts from the same place that will fit my bike?
1/5//2018 4:39:39 PM UTC
Ren - The Ed said :-
You'll need to find a Keeway dealer to get the front sprocket, they'll also sell you the rear and the chain. Again the MotoGB website listed above will guide you to your local dealer. On the page under Support you can find locate a dealer
2/5//2018 10:24:23 AM UTC
Ryan said :-
Cheers for that dude, they have the parts
10/5//2018 1:31:08 PM UTC
Ren - The Ed said :-
Wow! I can't believe I've been helpful :)
10/5//2018 3:37:57 PM UTC
Sean said :-
Will the keeway tx chain and sprocket fit on and work with the txm model
8/10//2018 4:44:00 PM UTC
Ren - The Ed said :-
Hi Sean. You're going to need to talk to your Keeway dealer. They are practically the same bike so I suspect they'll be the same - but! The rear wheel is different between the models and without looking at them it is possible the rear sprocket is different.

If you have not got a local dealer you can contact the UK importer via the link I'll add below...
9/10//2018 7:47:40 AM UTC
Kieron b said :-
Hey peeps im having trouble getting the nut off my front sprocket! The teeth on the spocket are well worn down and wont gaip the chain when i lock it up, but also the nut will not budge! Im turning it left as instructed by keeyway but the nut will not budge, iv tried everything
20/1//2019 4:03:19 PM UTC
Kieron b said :-
Any1 have any ideas..
20/1//2019 4:04:03 PM UTC
Upt'North said :-
Kieron, firstly I would put some freeing agent on there, plus gas or similar and let it soak in a while. Then give it another whirl, I take it you are trying with it in gear etc to prevent it turning. If that doesn't work then some heat may be required on the nut, be careful though you don't want to melt the seal behind. A plumbers torch would do it.
Hope it helps.
20/1//2019 4:34:08 PM UTC
Upt'North said :-
If none of those work, you could drill and chisel it off, obviously a new nut would be required and possibly a seal depending on your drilling skills, you may be able to fit a steel ate behind to reduce the effects of drilling and heat.
20/1//2019 4:39:15 PM UTC
Upt'North said :-
For ate read plate. Damn predictive text.
20/1//2019 4:40:13 PM UTC

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