Help with low top speed
Help with low top speed
I know this isn't the right forum for this but please bear with me. My buddy just picked up a 1989 Ninja 250. He is new to riding and wasn't comfortable on anything bigger.
Anyway, the bike only tops out around 70. This is AFTER I adjusted the valves, synced the carbs, and put a new chain on it. The bike is bone stock so it isn't a sprocket issue. It pulls real strong up to 70 but then just stops. There isn't any throttle left because it is pegged. I just don't get it and the Ninja forums are of little help to a Harley guy. The only thing they have said is that it should go at least 105 or I don't know how to shift right. Big help right! He doesn't want to go that fast but does want to be able to keep up and be able to pass on the slab. Thanks in advance for any suggestions.
Evan
Anyway, the bike only tops out around 70. This is AFTER I adjusted the valves, synced the carbs, and put a new chain on it. The bike is bone stock so it isn't a sprocket issue. It pulls real strong up to 70 but then just stops. There isn't any throttle left because it is pegged. I just don't get it and the Ninja forums are of little help to a Harley guy. The only thing they have said is that it should go at least 105 or I don't know how to shift right. Big help right! He doesn't want to go that fast but does want to be able to keep up and be able to pass on the slab. Thanks in advance for any suggestions.
Evan
Yeah 12pack that was one of the first things to come to mind but the throttle does operate fully. It ran ok before the adjustments but picked up some power after the carb sync and valve job. The valves were super tight so that made the most difference. I am almost leaning towards a clutch issue. The thing is that it pulls fine through all the gears although the sixth gear on that bike is basically useless. I'm no expert but do have some knowledge and this is driving me nuts!
Road Master
Joined: Feb 2007
Posts: 849
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From: where i'm at
Well my wife rode a 250 for a short time. I took it out once or twice and it NEVER came close to 100. Her's was an 06 I believe. I'm not sure that bike would be stable enough a 100. Come to think about it, I vibrated up around 70.
jim
jim
Mulch, it's pretty stable for a little 250. I adjusted the clutch this weekend and changed to a 15 front sprocket from a very worn 14 and managed 80 with a little throttle left. If he isn't happy with this I'm pretty sure he has some more room for adjustment in the clutch as it could be slipping slightly at high RPM. Thanks again guys for the suggestions.
Evan
Evan
Last edited by ecaldwell78; Sep 21, 2009 at 11:41 AM.
Road Master
Joined: Sep 2006
Posts: 899
Likes: 9
From: Franklin, TN
From what I read your pretty much on target with top speed around 80mph for a bone stock 1989. Even the new models, with work, are only getting to around 110/115 mph.
You didn't mention milage but have you checked the compression?
You didn't mention milage but have you checked the compression?
I was surprised to find the compression to be 122 and 126. It was either babied or rebuilt at some point as I was expecting 70 or so. I'm kind of leaning toward worn clutch springs and grooves in the basket. Easy fix if that is what it is. He doesn't want to throw a whole bunch of cash at it though because he wants a bigger ricer. So yesterday I told him if that wasn't enough for him we could take a look at the clutch springs and basket. If they are within spec then he would just be out the cost of a gasket and my beer. If not then he would be out the cost of springs, a gasket, and my beer.
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