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confused about jetting.....

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I changed the main jet of my 230 to a 132, and the pilot to a 45, and set my fuel screw to 1.5 turns out. When I put the carb back together and ran the bike, I noticed the pilot jet had slightly incresed the acceleration, but I got nothing from the main jet. The bike still went 66, which is what I clocked it before I changed anything......any suggestions?

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I changed the main jet of my 230 to a 132, and the pilot to a 45, and set my fuel screw to 1.5 turns out. When I put the carb back together and ran the bike, I noticed the pilot jet had slightly incresed the acceleration, but I got nothing from the main jet. The bike still went 66, which is what I clocked it before I changed anything......any suggestions?

I didnt know the jet kit was to make it run faster :cry:

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It isn't. Gearing will make your bike faster. Or higher r.p.m's, but I wouldn't recommend that. All that the jetting kit is supposed to do is make the bike run the way it is supposed to: Not lean. Plus, it adds a little more power. If you want your bike to have a higher top speed, then swap out your back sprocket, and put on a smaller one. Or put on a bigger front sprocket. But you probably already knew that... :cry: Just make sure that the chain has the right amount of tension.

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The thing jetting does is make the bike responsive and act like it's supposed to. A bike that is not jetted correctly will run hotter and will yield to a engine that will not last as long.

A properly tuned bike will also have more hp.

To gain speed, you will have to do the gearing like a user said.

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yes, I did know about changing the sprockets. But I've also heard the that reduces low end power of the bike. Thanks for the comments, i just read one time that the jetting was to make hte bike faster, so i was confused if i did something wrong. Thanks

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When your bike is properly jetted it should accelerate to top speed in less time. The terms faster and quicker do get thrown around losely.

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yes, it does reach top speed in a faster time, i was just expecting it to be "faster." but now i see. ok thanks

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When I rejetted mine, I DEFFINATLY noticed that it pulled more through the gears instead of plateuing out before I shifted to the next gear.

It seems happier and snappier!! :cry:

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Let me play devil advacate: Proper jetting could make you bike faster if: the main is off. Becuase instead of crapping out on top, if jetted properly w/ no rev limiter and a decent pipe it should rev to the moon, which should result in going faster. Yes? :cry: However, you guys are right when the bottom and mid are jetted right it's snappier, cleaner, resulting in the bike bieng quicker.

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That's good news. Now I have a question about high revs.

What is the actual RPM limit for bikes like the 150 and 230 before it gets too much for the little 4-stroke? A BBR(or equivalent) rev box will get you higher revs, but, looking toward the future, at what cost?

I understand 2smokes can rev around 13-14000. Some are saying the 4banger can too. Isn't that a bit much for these little bikes?

BTW, is this post stealing?

:cry:

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An XR100 can do close 15K. The only problem is floating the valves. Then you bend a valve, which could granade the piston, which could tear apart the combustion chamber, which could also, get in your piston pin, which ruins the rod, then various fragments get in the motor and tears apart the bearings and shift forks. Then you sell it on ebay, in "as is" condition and I buy it. (I've done this twice)

But if your lucky, it only bends a valve and knicks the piston.

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Four strokes of equal displacement(race engines) will typically rev significantly higher than their two stroke counterparts. Once a two stroke gets to a certain RPM, it can no longer "pump" air, so it stops making power at that speed. In the 60's, honda made 5 cylinder 125 four stroke's that revved to an unthinkable 30,000 + RPM !!!!

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I think the stock rev limiter on the bike is 9800rpm, it is on my bike and I think honda has it on the 150 and 230 also. They put that limiter on there for a reason and that is why so many people are not as happy as they thought they would be when they spend 60 bucks on the rev boxes. Most of the power on these bikes is down low anyway right?

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You are right. The stock engine is done making power before the rev limiter kicks in. A modified bike with a hi-rev cam will need to spin higher to make the power the cam was designed for. Most often with a sacrifice of low end power.

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Remember that these boxes provide a hotter advance curve. But then again, these bikes won't benefit from it that much :cry:

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