I have looked and it doesnt seems to tell me anywhere if I can squeak 5-10 out of the top.

I have a 2012 KLX205S and I love it, but would like a bit more speed for passing on these long straight Canadian highways between trails and towns. I seem to top out at about 65-68mph, with it now.

What are my options? if any.

edit, ill get this in first: ...besides getting a different bike.

 

351 Kit.

 

Drop a few teeth on rear sprocket, or add to front. 3 on rear is close to 1 up front. That'd be cheapest way.

 

Depends on your set up.

351 is the best way.

Get a slip on, rejet, and open up that airbox a bit and you'll likely get what you're looking for.

 

With jet kit, slip-on, MCM, and stock cogs, I could easily get over 80mph..

 

I don't remember if the Canadian bikes are injected, but if not after jetting and MCM, which pulls more mid-range where you need it, gear up to take advantage.

Go to a 15/39. Raw calculated speed will be roughly 10 mph faster at 7000 rpm than the stock 14/42 would run, being about 75 mph versus 65 mph. Fourth gear at 7000 rpm is at about 57 mph.

I could easily cruise at 70 mph, unless I hit a fairly strong head wind. I didn't shift into sixth until doing 55-60 mph. It won't give rocket launch power, but with a bit of prediction on your part - aka getting a bit of run up - you can usually drop a gear, nail it on the run up and pass. On a straight at 50 mph you can drop to fourth and still be in the power, then catch fifth and sixth in the pass.

But it isn't a big engine, don't expect miracles... there is no replacement for displacement. My 650 is loafing where my 250 is working... My friend's ZX14 is still in second gear!

For extremely close jetting click on the KLX250 Cheap mods in my signature. It was virtually plug and play for my brother (06) and I (09) at about 900-1000 ft elevation.

 

If you are running a stock set up go one down on the front (13t). It seems backwards but the stock bike will not pull redline in top gear. Going with taller gearing will make a slow bike even slower unless you are stage two or big bore. With the 13t you will will be able to pull more rpm in top gear i.e. higher top speed. And a front sprocket is less than $20.

 

If your bike tops out at 65-68 mph there is something wrong with it. Mine (EFI) is totally stock and does around 85 mph.
IMHO you just need to find out what's wrong with it and fix it. For the speed you are looking for no need for any tuning or big bore

 

First, you are right in some cases, like this one - IF the bike is pure stock.

There is a reason why it is hard to pull redline... the redline on the tach is about 1500 rpm higher than the true peak horsepower of the engine by Kawasaki's own rating. The horsepower rating peaks at around 8600 rpm. You are trying to rev harder as power is dropping off fast, you're "over the hill".

With the Marcelino cam timing modification (MCM) the torque and horsepower is higher across the range from 3500 rpm up to around 8000 rpm. Taller gearing allows the best use of the added power. With the MCM the peak horsepower and torque are higher, but at a lower rpm, the horsepower at around 8000 rpm. So gearing up is absolutely sensible, more sensible than over-reving the engine. It uses the power.

With the MCM and 15/39 if all the engine does is pull the 8000 rpm power peak it will do the same speed the 13/42 set up is doing at the 10,000 rpm mark on the tach - about 85 mph. Doing it with power it has gained within the true peak power range. If it could over rev to the fictitious red line it would be doing 108 mph. Does it pull the fictitious red line 108? I doubt it, my 650 has a tough time pushing that much air. Maybe with a down hill or going with the wind one might see an indicated three figures, but it ain't doin' it on its own.

That said, for what it is worth, I cruised at 70 - about 6500 rpm, not a problem - with the 15/39 sprockets, occasionally looking down and seeing 75 and backing down. It had more to go, no problem Will it pull 10,000 rpm in sixth? I don't know, I don't need it nor would I need the ticket. I just know it would buzz along with that set up. I use past tense because I geared it back down for actual dual sporting, the capability to go pretty much anywhere off road that a 250 dual sport might do. If anyone wants a deal on a 39T sprocket with about 100 miles on it, PM me. I don't need it anymore.

Like I said, I could easily run up to 55 in fourth and 65 in fifth with more to go before hitting power peak. This was a bike running the Marcelino cam mod, the KLX300 jetting changes to the stock carb along with the KDX200 snorkel, stock pipe. Maybe a pure stock one can't pull as strong. I'm thinking an EFI bike with the MCM would do the same as mine.

 

https://www.rockymountainatvmc.com/p...rocket?v=10211