Time to change out sprockets and chains

[AZRickD]

I noticed my rear sprocket has a bit of a wear pattern to it. The chain and front sprocket are original. The rear sprocket is an aluminum 50T that was put on shortly after purchasing.

It is a 2005 EC 250. We ride some technical stuff out here which is the main reason the former owner put on the 50T.

After having ridden it for several months, I'd like to consider a 51T or 52T to make second gear a little more useful in some semi-tight trails. Is the 51T a big enough difference for my application? Will 52T be too much? Will I find myself spinning the tire too much with a larger rear sprocket?

What are good bang-for-the-buck chains (O-ring) and sprockets?

Thanks,

Rick

 

[2 strokes 4 life]

Are you wanting to make the 2nd gear bigger or smaller? I switched from a 48T to a 50T and i still find it not a huge difference. I think you are better off with a 52T.

 

[eff]

I run a 52T JT rear sprocket and Regina Gold O-ring chain. That combo holds up real well and the 52T is great in the rocky NE woods.

 

[PEB]

13/49 is the magic combo for tight stuff. I have had excellent resultd with the Rocky MT deluxe "o" ring chain for about $50. I always try to run steel sprockets and the chain is generally good for the duration of one rear and two front sprockets.

 

[AZRickD]

I think you are better off with a 52T.

I need a bit more of a granny gear out of 1st. This will also make 2nd gear more usable. The areas I'm talking about are long rock gardens through our numerous dry washes, as well as those pesky uphill switchbacks where I have to carry the clutch more than I'd like.

If it turns out to be a bad move, I'll get a different one.

I don't want to use steel because of the extra unsprung weight out on that pendulum. The difference is really noticeable. I'm prepared to give up some longevity.

 

[joey11]

I run ironman 13/51 and it seems to be a great combo with a Regina 0-ring. Probably 65-80 hrs on the sprockets and still good. I do wish sometimes that second gear would last a little longer without the need to switch to third, so I just bought a 50T sidewinder on fleabay for cheap to try. I'll post results. Does anyone know if I can run one link less with the 50T. I am already near the end of adjustment on the swingarm with what I'm running now. I'd like to shorten things up to make is turn sharper. Would this help?

 

[Skidad]

At least get the Ironman front until you decide finally on the rear size you're going to use. 13/52 seems pretty common for the 250's in gnarly terrain. It's what I use on my KTM 250 EXC as well for New England.

The rear Ironman you will not believe how light it is. I had been using a Stealth sprocket but will be using the Ironman from now on. Good stuff.

 

[2 strokes 4 life]

I must not be ridding enough tight stuff because i think i am going back to a 48T over the winter because with the FMF Gnarly it pulls alot more on the bottom and mid than the Messico did.

I am sure with the RB-desinges Mods will add alot of bottom as well so i think the 250 should pull it fine. I am going to also lose some weight over the winter so that should help too.

 

[dave948]

You can't beat the Ironman sprockets. As said they are very light and will last forever.(3 chains is normal service life)

My bike had 12/48 when I got it. I rode it like that for a month or so then at the suggestion of the previous owner I changed out to 13/50. To tell the truth I can't really tell the difference. He said it would soften the hit a little but it feels the same to me.

I may try the 12/50 as I have the sprockets but this is opposite of what I was told I should do. The previous owner was alot faster than me.

 

[AZRickD]

I ordered the new Renthal front sprocket from GoFasters. He said they had just gotten Renthal to import them for the Gasser.

The YZ250 and CR250 sprocket didn't match. Gas Gas USA was unaware of any cross-reference.

I took off my front sprocket and examined it with the chain off which shows a lot more perspective. It's definitely warn. I went with a Moose aluminum rear sprocket to see if I like this ratio. Chain is a DID X-Ring.

 

[iancp5]

I have a theory that for off road the standard gearing is very, very close. Ok you may want to add a tooth or two on the rear but no more. I played around on my 300 and ended up deciding 13/48 was best. If I went to a 12 1st gear became redundant and unused as it was too slow and too jerky. For the really slow bits I was better off with a 13 and slipping the clutch. Some say 13/49 is spot on - ok maybe but I doubt I could tell the difference.

If you find you're spending a lot of time revved out in 6th maybe you do need to change. If you find first is too high you need a different bike.

You have 6 gears and the idea is to make them all usable without always needing to slip the clutch.

 

[gasser]

The perfect gearing is a very important and very personal thing that is affected by many things : type of terrain, riding style, weight, size of motor, and how the motor is tuned. That last item is often overlooked by many of us. A motor that is running too rich will feel weak and sluggish and therefore respond better to lower gearing. It would be best to get your motor running properly then experiment with different gearing ratios at your favorite riding area. As a general rule go up 2 teeth on the rear sprocket each time you go down 50cc on the engine size. Since you like the 13/48 combo on your 300 you would probably like a 13/50 combo on a 250 and a 13/52 combo on a 200.

 

[AZRickD]

I've had several people ride the bike when I first got it last winter. When I told them I was considering a bigger rear sprocket they thought it was geared a little low already. So I gave it a go.

Sorry. It's time to do things my way.

I don't use the gear box the way it was intended. If I get out of 2nd gear around here I get all giddy. Fourth through sixth is for transfer sections and forest service roads whose only purpose is to get us to the next section of rocky single track.

If the 52 turns out to be too blippy, I'll try a 51. I have a race the weekend after next. I'll give a report.

 

[Skidad]

I think you'll be happy with the 13/52. Many of the KTM 250 guys run this for tight terrain and even though the GG has a 6 speed tranny it's overall spread is actually just a smidge less wide than the KTM XCW's 5 speed so they do compare really. KTM tends to be gappy stock though so you get the XC vs XCW tranny wars on KTM Talk. Ask any KTM 250/300 owner and they dream of a 6 speed tranny.

Nice choice on the chain but I still would have gotten the Iron Man front from Dirt Tricks in NV.

Let us know how it works out for you

 

[iancp5]

The perfect gearing is a very important and very personal thing that is affected by many things : type of terrain, riding style, weight, size of motor, and how the motor is tuned. That last item is often overlooked by many of us. A motor that is running too rich will feel weak and sluggish and therefore respond better to lower gearing. It would be best to get your motor running properly then experiment with different gearing ratios at your favorite riding area. As a general rule go up 2 teeth on the rear sprocket each time you go down 50cc on the engine size. Since you like the 13/48 combo on your 300 you would probably like a 13/50 combo on a 250 and a 13/52 combo on a 200.

Funny you should say that. I now have a 200 with 12/48 which is much the same as 13/52. The 200 gives me a low enough 1st without yanking my arms off if I so much as twitch the throttle a few thou! For the guy that never gets out of 2nd gear I would seriously wonder if a 300 is the right bike. But ... ultimately it's what you enjoy that counts. Sounds like apart from the transfers you need a trial bike. I switched to a 200 because I was hardly ever getting the throttle open on the 300. Now I find I use the whole range of throttle and gears in most races. I'm a bit slower at the start but a bit faster at the end and don't feel like death when I finish. I'd quite like to try the KTM 250 EXC-F but I've been told we have to decorate the house first.

 

[AZRickD]

I put my riding buddies through hell over the last year trying to find a replacement for my Dangerously Modified (tm) KDX220R. I was test-riding every bike I could find. I was very close to getting either a GG300 or a KTM300 if I couldn't find a GG. It really suited my sucky riding style and rocky hills. However, the more I rode 250s (be they GG, KTM, YZ, or Huskies) the more I decided I had more fun on them. I knew I'd pay a price but that's what I did.

I also jumped on a few 200s. I'm just not a good enough rider to make the most of the 200. I had to use every bit of clutch and RPM to make the thing go. I was always behind the curve. It would have taken me months to figure out how to ride it.

I got all of the parts, but I'm still waiting on the front sprocket I ordered from GoFasters to get here. Shoulda been here Friday or Saturday, so with a race in five days, I'm getting a little anxious.

Edited to add: Got the sprocket.

I have the day off tomorrow to put it together.

 

[AZRickD]

Me likey. I did a short ride over non-technical stuff. I can't wait to get it to some tight, switchbacky, hill-climby single track this weekend.

 

[AZRickD]

Did the race. Loved the ratio. I was able to loft the tire better. Perhaps the flywheel weight slowed things down a bit. While none of the hill climbs were particularly challenging, needless to say, there was no clutch feathering going on.

I did break my pinky due to an out of control rev situation. It wasn't a stuck throttle, however. It felt like a Cox model airplane going lean from lack of fuel.

I'll start a new thread on that later.

 

[SpeedyManiac]

My gearing thoughts:

For my 200, I run 13/52 since it doesn't make huge bottom end. On my 250, I run 13/48/49/50 depending on the terrain. The 48 for fast stuff (ISDE, desert, etc), the 49 for a mix and the 50 for the tight stuff. My ISDE bike had 13/48 and was fine even on the technical stuff. The GasGas engine makes so much bottom end (you do have a LTR PV cover, right?) that stock gearing works surprising well. Around home I tend to ride tight, technical stuff and the race series here is very nasty so I add a couple teeth so I can stay in 2nd most of the time.

I think 13/52 or 12/48 would be too much for a 250. It would be very hard hitting and top out too quick.

 

[AZRickD]

Yep. I have the LTR cover and Power Now (both sides). Maybe next summer I'll get the R-B Designs squish mod when I do a top end (had the pipe, carb and squish mods on my KDX).

I'm glad I did the 13/52. It suits my lack of skill just fine. It felt like I had the KDX gear box again (13/50). I can see 13/51 working better, perhaps. Maybe next time (it's aluminum, after all).