So im trying to figure out if my 97 kx 125 just has a crappy powerband or if there is actually an issue. The power seems to come on then peak and drop off rather quickly. My 93 once you hit the power it feels like it pulls forever. I want that feel on my 97 and was wondering if reeds would make a difference? Im gona replace em today cause theyre only 30 bucks but any other suggestions? My buddy said to take off the fatty pipe and go back to stock and that would help but i dont have a stock pipe.
Will reeds affect top end power?
- Thread starter kawraper
- Start date
helio lucas
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- Jun 20, 2007
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rule of thumb: stiff more top, soft more low end...
maybe boyesen dual would be better as they work good for low and top...
do you try to jet the bike first?
maybe boyesen dual would be better as they work good for low and top...
do you try to jet the bike first?
- Thread starter
- #3
Yeah im pretty sure its jetted right. The reeds that are in it now felt pretty slop. I got the new ones in the car so when I get caught up here @ the shop Ill toss em in see if it makes any difference. I got the boysen duals i believe.
And going by your rule of thumb the bottom feels great. Best bottom on a 125 2 stroke ive felt. But I dont want to sacrifice all the top end for it either. Im willing to loose some bottom to gain some top.
And going by your rule of thumb the bottom feels great. Best bottom on a 125 2 stroke ive felt. But I dont want to sacrifice all the top end for it either. Im willing to loose some bottom to gain some top.
- Thread starter
- #4
well no go. Still the same :( It looked like it was running a little rich so I dropped the needle got it lookin good but still lacking the top I like.
Id suspect the powervalve but the way the power hits Id say thats not the problem.........any other ideas?
Id suspect the powervalve but the way the power hits Id say thats not the problem.........any other ideas?
allUseeisRoost
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- Apr 13, 2009
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the powervalve should be adjustable ... softer/stiffer springs engage the powerband differently i think softer is lower rpms and stiffer is higher i could be wrong tho
how many hours on your top end??
how many hours on your top end??
- Thread starter
- #7
Dont know the hours on the topend, has good compression though. Yes I read the plug.
I opened up all the powervalve linkage and found the one arm was disconnected. So I hooked it back up and secured it. Now it feels like theres even more bottom end but still the same crap top end.
Im puzzled at this point. Maybe the 97s just have crap for topend power. Or maybe its the stupid fmf fatty pipe robbing it all away.
I opened up all the powervalve linkage and found the one arm was disconnected. So I hooked it back up and secured it. Now it feels like theres even more bottom end but still the same crap top end.
Im puzzled at this point. Maybe the 97s just have crap for topend power. Or maybe its the stupid fmf fatty pipe robbing it all away.
helio lucas
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- Jun 20, 2007
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is your carb clean?? air filter? new plug? engine in good overall condition?
is it ported before? over advanced ignition timing?
is it ported before? over advanced ignition timing?
- Thread starter
- #12
I read the plug by doin a wot rip in gear on the stand then kill it and check it.
Cleaned the carb, new air filter, new plug, ive messed with timing just too see if it would make a difference. Good compression.
Dont know whats been done to the engine and really dont want to crack it open to find out. Looking through the exhaust port piston and ring look brand spankin new. The bike overall runs great I just want to unlock that little bit of top end power i feel its missing and it will be great. The low end is pretty insane now for a 125.......
Maybe I just need to go with a biggier sproket now up front so the power lasts a little longer.
In all reality i just want my 93 back....that bike rips.....this 97 has got nothing on it. Im getting impatient on my parts to rebuild it.
Im gonna repack the silencer and if that doesnt do it im gona have to assume the 97 just has a crappy top end.
The 97 only has 2 smaller powervalve ports where as the 93 uses 4. Probly like 25% more flow for the exhaust and id have to assume thats why it has so much topend that the 97 prolly never will have.
Cleaned the carb, new air filter, new plug, ive messed with timing just too see if it would make a difference. Good compression.
Dont know whats been done to the engine and really dont want to crack it open to find out. Looking through the exhaust port piston and ring look brand spankin new. The bike overall runs great I just want to unlock that little bit of top end power i feel its missing and it will be great. The low end is pretty insane now for a 125.......
Maybe I just need to go with a biggier sproket now up front so the power lasts a little longer.
In all reality i just want my 93 back....that bike rips.....this 97 has got nothing on it. Im getting impatient on my parts to rebuild it.
Im gonna repack the silencer and if that doesnt do it im gona have to assume the 97 just has a crappy top end.
The 97 only has 2 smaller powervalve ports where as the 93 uses 4. Probly like 25% more flow for the exhaust and id have to assume thats why it has so much topend that the 97 prolly never will have.
helio lucas
~SPONSOR~
- Jun 20, 2007
- 1,020
- 0
you just can´t read a plug with the bike on a stand, do not have load enough... that´s why it is make in the last gear... but it may give you a ballpark (a nasty one)...kawraper said:
is your power valve working correctly?
http://www.eric-gorr.com/model tuning tips.pdf
http://www.eric-gorr.com/2 stroke top end and performance.pdf
take a look ;)
honestly, if you are sure every thing is fine, including jetting, then it should be a cylinder (porting) problem...
if you want, just inserting a thicker base gasket say, 0.5 mm to 1 mm will exchange bottom and midrange to top end power or over-rev... :cool:
- Thread starter
- #15
Well from what i gather i should get a differen reed cage like the one off my 93. I already tried and knew it would take case grinding to get it to fit. Next would be the pipe.
I need the reeds for my 93 its getting rebuilt next week. And Im not trying to spend 300-400$ on a new pipe/silencer setup. Looks like Ill just have to learn to ride it the way it is.
Oh well my 93 will be up and running soon I guess ill just have to ride that bike to get the power i want.
I think next season i will just sell the 97 and look for a 250, I think thats really what i need.
I need the reeds for my 93 its getting rebuilt next week. And Im not trying to spend 300-400$ on a new pipe/silencer setup. Looks like Ill just have to learn to ride it the way it is.
Oh well my 93 will be up and running soon I guess ill just have to ride that bike to get the power i want.
I think next season i will just sell the 97 and look for a 250, I think thats really what i need.
