Top End Power loss

All Engine, Clutch, Chains, and Sprockets Stuff Here.
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kkvslayer
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Top End Power loss

Post by kkvslayer »

I posted this on the "other" site and got nothing hopefully someone on here can offer something

So a few days ago I was rippin around and my gnarly pipe that was already cracked and welded broke in two pieces,so I cut a piece out of that and welded it over a hole that blew out on my stocker,the hole was on the inner side right by the forward mount maybe a three inch sqaure hole but it is completly covered and welded,I had this pipe on for a while before I tore My engine down and it was fine till I blew the hole in it,well it was nothing like the gnarly but it worked,the pipe is pretty dented up,anyways if you just whack the throttle it'll pull for a few seconds then just gets loud and boggy,sounds like crap,If I roll on the throttle very slowly it will pull but once it gets on the pipe it gets that same ugly sound,also I noticed the engine braking feels stronger when I roll off the throttle then when the gnarly was on there,I tried going down to a 172 from 175 on the main but its still the same,anybody ever experienced this just from a crappy pipe or do I got issues elsewhere?
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dannygraves
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Post by dannygraves »

your running lean, put a 178 in there and move your needle down a clip and see how it goes. FMF usually recommends going a step leaner. Also, if the pipe isn't sealing to the exhaust manifold, that will leat air in and get a similar problem. defin itly sounds like a lean condition to me though, be CAREFUL, I'd hate to see you squeek that shiney new motor!
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Post by dannygraves »

My bike did something very similar when my reeds werew worn, might have just happened at the same time. When did you last replace your reeds?
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kkvslayer
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Post by kkvslayer »

I broke the fmf & patched the stocker and put it on thats when It started doing this,I changed the jet yesterday,I also put a DGN needle in & nothing changed,If I pull the clutch as soon as I let off the throttle the revs calm right down with no surging,Its when I don't pull the clutch during decel it feels so funny,I havn't checked my reeds since I put them on last winter,will do tonight,I didn't put my new walls and piston in yet,the old piston & walls just looked to good to replace yet,I'm plannin on sendin my jug to that shop ou812 recommended this winter
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Post by ou812 »

Sounds like you ate some reeds, but I would never run a gnarly on a 85 or 86. Get a good used stock pipe or as a second best bet get a pro circuit.
also repack your muffler if it is wet and soggy it can cause problems.

As a side note even stock pipes of differant years have a amazing differants, my 87 motor in the 87 bike with the stock pipe had a real hard hit in one spot, when I put the 87 motor into a 2000 roller with the stock 2000 pipe it totally changed the power spread.
kkvslayer
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Post by kkvslayer »

Geez I really hope its just my reeds,I'm tired of wrenchin on this thing,hopefully I can just pull my vforce block and throw my stocker back on,thanks for all the ideas I'll let yall know what I found tomorrow
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Post by britincali »

This is gonna sound stupid but trust me Ive been there.


CHECK ALL ELECTRICAL CONNECTIONS

I was told this over and over and checked a few easy accesable wires to find nothing, one time is was a wire from the CDI hanging off and the other was the spark plug tip unthreded. In both cases the bike ran fine at idle but wouldnt open up unless slowly revved up.

It took me a few trips to find both of these issues.
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Post by dannygraves »

that happened on my old 125, loose coil wire.
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'05 klx110 --SOLD--
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Post by kkvslayer »

ya know what now that I think about it last week I fired her up was letting it warm up I had just put my pipe back on and never tigtened the front mount so I reached under to hold the nut on touched the plug and got a pretty damn good shock but never thought nothing of it I wanted to ride so I just shut my bike off and tightened the bolt and fired her up and took off,I'm gonna check my electrical too
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Post by ou812 »

If you got a shock off the pipe then you do have a bad ground issue.
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Post by kkvslayer »

ou812 wrote:If you got a shock off the pipe then you do have a bad ground issue.
I'm not sure where the shock came from I was reaching under the tank from the left side to hold the nut while i tightened the bolt for the front mount on the pipe my fingers were touching the bolt but I got shocked on my wrist,it left a good size red mark for a few hours,if its a bad ground could it cause the symtoms I described?
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Post by ou812 »

I've never ran into that problem but a partcial ground would do that, also check your coil lead, it's probly hard as a rock and can really screw things up.
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Post by kkvslayer »

Finally had a chance to have a look,heres what I found-Reeds still look the same as the day I put them on,I cleaned my ground made sure all connections were clean & tight,tried richening my needle to the 5th clip,still boggy & unresponsive after 1/2 throttle,I'm runnin a 172 main with a DGN Needle,honestly it feels rich to me but if I go By the book I'm already runnin stock jetting & kind of scared to lean it out anymore,I'm not sure what to look for from here on the only thing I can think is that its from the pipe but I don't know if it would cause as much of a power loss as I'm getting,seriously my bike is kind of boring right now,its not makin me grin like it used to,I wanted to shoot a vid yesterday and post it up so you guys could see & hear what I'm experiencing but never got a chance to get it done,maybe tonight after work,ou812 can you explain a little more about the coil lead.thx guys
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Post by kkvslayer »

Oh yeah I also checked under the left cover for a leaky seal,all dry
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Post by dannygraves »

change that needle to the 3rd clip, I've got porting work and run a 58 pilot, dgn 3rd clip and 182 main. I tried my dgn at the 4th clip and it was blubbery from 1/2 to 3/4 throttle. if it gets boggy past 3/4 then you have to fatten the main.
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Post by kkvslayer »

dannygraves wrote:change that needle to the 3rd clip, I've got porting work and run a 58 pilot, dgn 3rd clip and 182 main. I tried my dgn at the 4th clip and it was blubbery from 1/2 to 3/4 throttle. if it gets boggy past 3/4 then you have to fatten the main.
I'll try that out after work,I'm kind of confused about jetting :? If its boggy then isn't it rich?shouldn't I need a smaller main? In your case in the nevada heat shouldn't your main be way smaller then a 182?
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Post by dannygraves »

kkvslayer wrote:
dannygraves wrote:change that needle to the 3rd clip, I've got porting work and run a 58 pilot, dgn 3rd clip and 182 main. I tried my dgn at the 4th clip and it was blubbery from 1/2 to 3/4 throttle. if it gets boggy past 3/4 then you have to fatten the main.
I'll try that out after work,I'm kind of confused about jetting :? If its boggy then isn't it rich?shouldn't I need a smaller main? In your case in the nevada heat shouldn't your main be way smaller then a 182?
"boggy" is waayy too lean. you will mostly run into blubbering situations which are rich.
In the nevada heat I should require leaner jetting, but after my porting work and higher compression, I require more fuel. which is the paint I was trying to get across... I need a 182 main and 58 pilot, but anything more than 3rd clip on the dgn is too rich for me.
'09 kx450f 4-Poke
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Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80
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Post by kkvslayer »

:shock: I got alot to learn I guess,I just got a set of jets too & the highest # I got is a 175 :x ,I gotta order some more jets I guess,thx
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Post by kkvslayer »

I figured it out,I just had to move my clip further up on the needle,Its on the second one & the throttle response is waaay crispier,my master link came off last week though so now I'm waiting on a new chain,at least my case saver did its job,I just got a few little scratches on there.
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Post by britincali »

I ran a 185 at dumont this weekend and im pretty sure I was rich, im slapping in a 175 for the trip in 2 weeks.
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Solidbro = cool
Brit = loser
Stoffer = 1 up from Brit
MFDB = cool
Danny = ok
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