HH250 no power
 

alright guys here we go. its an 07 hasn't ran for a while. i finally got to it. i changed the CDI had to put new wiring harness on it. after that it ran but only hits like 28 mph. i put it back together and this is where im at. it fires up and runs great for about ten minutes. then it starts back firing. and if i hit the gas it will bog down. i was going to adjust the valves but i don't know where thats at. adjusted the air screw on the carb and it seemed to help but not all that much. the carb has just recently been cleaned and new gas filter. my air filter is dirty but i plan to fix that. ever since we bought this its had no speed and no power. HELP PLEASE! i want to get this thing to be a beast!

oh and i planned to get the performance exhaust with the cold intake and the jets and rollers. i have the rollers and i was told not to rejet the carb till i got the performance exhaust.

before you invest any money in parts, get what you have dialed in. you should be able to find a downloadable owner's/service manual that'll have the info you need to check the valve settings and adjust if necessary. you may also need to inspect for intake or exhaust leaks. both of those items are pretty simple to do and if there's an issue with either, fixing them should improve things ....

well the owners manual is a joke. but im gonna adjust the valves just gonna have to play with it. but the exhaust is flowing pretty good. its pretty rusted and in need of a new one but that doesn't explain it backfiring AFTER ten minutes of runnin good. thank you!

Sure it does, the valves need adjusting. After the valves warm up, they expand so the gap tightens and they won't close off completely. The back fire indicates the exhaust valve especially. A hiccup through the intake would indicate a intake valve . there are many tutorials on the web showing the process for correctly setting the valves.
OR.. your cdi is going bad. resistance in the internal circuitry is taking 10 minutes or so to heat up enough to alter the timing signal.

If you go to Buggypartsnw.com there are step instructions on how to set the valves on a 250 cc motor. :hooaray:

ok.. so Rich1.. that site is AMAZING. its gonna help me when i put my performance exhaust on and rejet my carb. your awesome. unfortunately i cant "test run it" till monday hard to find a place to run it around my city without getting caught! get back to you monday!

oh man and the performance package is so much cheaper.. now as i said im not too familiar with carbs. whats the difference between the stock carb and this 32mm pumper carb..?

last but not least anyone know where i can get the vacuum line assembly for the HammerHead SS250. im looking everywhere and i got nothin

In addition to the carb being larger than the stock one, it has an accelarator pump in it . Everytime you step on the gas pedal it shoots a small stream of gas through the carb. This stream of gas will make youre throttle responce almost instant. You can also use it to richen up the mixture before you start it to make it start easier too.:

As for the vac lines any HammerHead dealer can order them for you .Look on their website" Hammerheadoffroad.com" for a local dealer since they only sell parts thru them.:biggthumpup:

i mean where they all go. there is one line specific wasn't connected for a looong time. and i found a port to where it would go but honestly if its running and you pinch the line it doesn't do anything. obviously i pinch other lines and it will start sputtering so i just want a diagram of where all the vac lines go coming from the carb

welll.... i got it to run 35 mph and its never gone up that high.. but im still having the stalling issue.. im thinking its just the carb it was filled with sand and then ran and ran i think its just shot

Did you see sand in the bowl of the carb when it was cleaned? or was the sand just around the air inlet?If sand was inside the bowl area- How long was it run before the carb was cleaned? If sand made it into the carb,then it probably made it to through the intake valve & into the piston & cylinder- Have you done a compression test? this may be the reason for "poor performance".

yeah i was gonna do a compression test but i dont have one that fits inside the sparkplug area. the testers i have are for cars. and i dont know i didnt clean it i had someone do it but what happens if it made it through the intake valve and stuff? and they junked?

Sand/dirt will scratch the cylinder, damage the edges of the piston, deposits can land on the piston causing hot spots(possible hole in the piston,pre-detonation), deposits at the valve guides not letting the valve close properly. These issues lead to- low compression,oil burning/smoking- Does it smoke? if so-what color?

nope doesnt smoke at all it jus stalls out now i tried adjusting my valves just a tiiiny bit but then it didnt start at all im getting a new performance carn and exhaust so thats my last option