Can I get away with a 104 link chain with stock gearing? If not, what rear sprocket?

[CZroe]

I see some sites that try to sell me a 104-link chain when I specify a Ninja 250. I think it's because the 1986/1987 model may have been 104 links.

The specific chain I want for my project bike is not currently available in 106+ lengths but is available in 104. With stock gearing, is there enough adjustment to get away with 104 links? If not, how small would I have to make the rear sprocket to get away with it? Perhaps I can do 13:42 to keep a similar ratio with smaller sprockets.

Yes, it seems silly to consider spending money on sprockets to fit a particular chain, but this bike only exists for this purpose (style concept).

[alex.s]

i can never find the right length. i buy a 116 or 120 because you can find them everywhere then just remove the extra links. i think you need a 106. stock rear sprock is 45 so -2 links would be 43 tooth i think... dont trust me, im wrong.

[DaBlue1]

I've tried a 15/39. 15/39 requires a 104 (or shorter) link chain, however that ratio has it's limitations. Hills may be a problem and the engine will not pull past 11.5k in 6th.

[CZroe]

Originally Posted by alex.s

i can never find the right length. i buy a 116 or 120 because you can find them everywhere then just remove the extra links. i think you need a 106. stock rear sprock is 45 so -2 links would be 43 tooth i think... dont trust me, im wrong.

That's exactly what I do. The problem this time is that there are none available over 104 links, so I'm wondering if the adjustment alone can handle it or if I have to get a smaller sprocket.

Originally Posted by DaBlue1

I've tried a 15/39. 15/39 requires a 104 (or shorter) link chain, however that ratio has it's limitations. Hills may be a problem and the engine will not pull past 11.5k in 6th.

Well, I crossed the country on 15:38.

[DaBlue1]

Originally Posted by CZroe

.....Well, I crossed the country on 15:38.

How did the bike do?

[CZroe]

Originally Posted by DaBlue1

How did the bike do?

Well, it was kind of an emergency swap from a couple weeks earlier and my experience has been kinda mixed:

My chain was losing the rollers on the pins and the cracked up or C-shaped remnants were chewing up my new rear sprocket (can't recall if it was 42 or 43 tooth). I was hours away from home and late for work, so I took the only one that was in stock locally and swiped a forum members OEM chain. We used a chain breaker/maker tool and removed a couple links. On the way back, I was in a hurry and found myself hitting the same top speed I always hit (a little over 100MPH indicated; probably 89-91 actual speed). Over the next couple weeks it was fine and seemed about the same as my 15:41 setup from the previous year. I hit 100MPH indicated routinely when commuting daily. I really felt it was fine, until I did the cross-country trip in under 45 hours. I was obviously in a hurry to unintentionally qualify for the Iron Butt 1000, so I needed to maintain speed and found myself dreading any kind of incline. For some reason, I had a lot of trouble maintaining a 50MPH+ speed up a hill and would try to speed up as much as possible before encountering them. This really confused all the cars that I would fly past and then fall back behind at 48MPH. I dunno why, but I did not have that problem in SoCal at all. I would blast down I-15 and CA-163 and on through down-town daily, pass cars, and maintain speeds uphill just fine. I don't think elevation has much to do with it: I remember the non-mountainous hills in Eastern Alabama being particularly rough. I was horrified after arrival when I found that the used OEM chain did the same thing to my new sprocket and was also cracked and missing rollers.

Edit: Just thought about how my newgen bike has a 41T with a 106-link chain. Might be kind of tough to fit with 14:41 on a 104 link chain, but it means that I can switch sprockets between the two bike if I have to. I'd rather avoid buying more sprockets. Hopefully a previous owner didn't already throw a 15T on the front.