She Won't Rev Past 8000!!!!

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Marty_Rillo
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She Won't Rev Past 8000!!!!

Post by Marty_Rillo »

hi guys, still getting this bike up and running and i seem to have encountered a problem.
It starts like dream and pops away but as i snick it into gear and twist the throttle i get lots of noise, no power and then hits a wall at 8000rpm and wont go any further.
every thing seems right to me, so im guessing carbs or electrical?
i have replaced the regulator and it didn't change a thing.
It was a basket case and had sat for a while but i have been pretty carefull!!
any help will be much appreciated!!
cheers
martin
garye345
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Post by garye345 »

Power valves.if not,try decoking the exhaust.
If it is'nt those :?,
over to someone else :arrow: .
I used to be so care less,as if i could'nt careless.
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ScottaKR
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Post by ScottaKR »

Agree with Garye 100% on that.
The other thing that can cause this is if there is no air filter support fitted or it's damaged which can allow the air filter element to get sucked into the carbs.
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scooble
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Post by scooble »

does it rev out in neautral, or only when there is load on the engine?

check that the float boals aren't running out of fuel by checking the float and needle valve. check that the fuel tap is flowing enough fuel.

check the air filter (as mentioned before)
Check plug caps are in good order and on tight.
Feel the exhaust after if has been running poorly - which one is hottest?
Check compression on both cylinders.
yatasaki
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Post by yatasaki »

used to run mine with kips closed over 8000 (cdi problem), still able to do 180 kph
i would say stingers clogged
but as above as well
Luders
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Post by Luders »

Hi Martin,

Does this happen under load?
mgtkr1
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Post by mgtkr1 »

if its under load, but ok in neutral id look at the stator/coil even plug caps. ie anything electrical. if its the same wether it be under load or not then look at the carbs. poss a main jet has fell out. as daft as it sounds, are you sure the carbs had mains in? another idea is to check for a fuel blockage starting with the fuel tank breather, fuel tap and work down to the carbs. also be aware of kinks in the fuel pipe. another suggestion is make sure your pipes are clear. recently seen someone with a similar problem. while the bike was in bits a mouse decided to set up home in the pipe!! also check things like airbox and the filter. the filter can become dislodged and block up the carb inlets owed to a flimsy filter holder.remember, the basic things you need are air/fuel and a spark.
Bertie_Mollie
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Post by Bertie_Mollie »

I put my money on exhausts as Gary and Yatasaki have suggested.

As ridiculous as it sounds it happened to me and took months to get to the bottom of :oops:

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Marty_Rillo
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Post by Marty_Rillo »

Thanks guys for the help.
It happens if its in gear or not. i did wonder about fuel starving so i will check that out first.
The exhausts were as clean as a whistle but the tail cans are quite an unusual design, they look a tad home made but i have no idea if the bike ran well with them on or not.
i did wonder about carbs as the bike will just die if i open the throttle full when its idling!!
So thanks again!!
Martin
headcoats
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Post by headcoats »

Is the diameter of the end cans the same diameter of the stinger part of the expansion chamber ?
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Luders
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Post by Luders »

Check your jets Martin, they are probably blocked. Make a note of the sizes whilst you're there too.
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