Jump to content

need help jetting milled head made me slow!


Recommended Posts

I just got a milled head and it made my banshee much much slower. it was freakin unbelivable how much top end was lost! and mid was hurting too.and bottom end power gained nothing but nothing seemed to be lost. i think maybe it has something to do with the jetting. i have fmf fatty pipes and a K&N filter. i have 200 main jets in now. i live in the st louis area (not sure what the sea level is) any input is appreciated. hopefully someone has a answer. because i dont really know much about jetting. thanks

Link to comment
Share on other sites

I just got a milled head and it made my banshee much much slower. it was freakin unbelivable how much top end was lost! and mid was hurting too.and bottom end power gained nothing but nothing seemed to be lost. i think maybe it has something to do with the jetting. i have fmf fatty pipes and a K&N filter. i have 200 main jets in now. i live in the st louis area (not sure what the sea level is) any input is appreciated. hopefully someone has a answer. because i dont really know much about jetting. thanks

353189[/snapback]

 

The reason you lost so much is you were already way lean with having pipes so your cyls are running hot now you have it more compression so that heat is making you detonate resulting in lost power. I would take the needle up one clip and start with a pair of 260 mains and go from there. also post how much your head was milled and if the macine is ported you may need to run some better fuel someone on here will be able to tell you what octane to run with that info. hope this helps

Link to comment
Share on other sites

Thanks for such a fast response. im glad someone else thinks it jetting too. i was scared it was something serious. Im not exactly sure what the head has been milled to... I bought it off a well known engine builder in this area. Ritter cycle here in il. He wouldnt tell me the exact number of what was milled off said it was his "secret" and i feel stupid now for not making him tell me what i was buying... but anyways I asked if it was more than 30 onethousands and he said it was more he said it was enough that he had the around the domes clearenced so the pistons would not hit. He was saying something about stock the banshee should have around 120psi and with this head it should have around 150 or 160 something like that..thanks again

Link to comment
Share on other sites

you can still check the CC of the chamber on that head

 

go to a farm and fleet rural king or farm king wichever is closest to you

and go to the pet care section

get yourself a horse syrenge

 

yeah the big thing they use to give a horse its shot

the syrenge without the needle is perfect for measuring the volume of stuff like this

 

if you ever have the head off or have a spare gasket to take it off

then just thred a spark plug in the hole and fill the chamber with liquid that you measure from the big syrenge

 

stock head i think is 22-23 CC

 

hey where in IL is ritter cycle at?

Link to comment
Share on other sites

200 mains!! with k&n and aftermarket pipes.

i wouldnt ride that thing another 100 feet. it must be about to explode with the much higher compression now!

 

depending on your elevation i would start with 300 and work your way down from there..its always better to be rich on your jetting.

if you still have the stock needle in then go up 2 notches.

 

There are a few good guides about how jetting works.

Link to comment
Share on other sites

200 mains :whoa: If you still have your airbox and a lid, 280 might be close. Starting at 300 wouldn't be a bad idea. Since you dont know how much was shaved off the head, a compression check should be done. You might need to run a 50/50 mix of race fuel and pump gas.

 

Oh yeah. The sea level is about 600 ft. below you. :D

Link to comment
Share on other sites

thanks for all the help. i just went out and bought an assortment of jets between 260 and 300. i cant try them yet tho because i cracked (fractured) my damn swing arm! and the edge of my axle carrier is damaged also. whenever i get this all fixed im going to work on the jetting. thanks again

 

PS ritter cycle is in st jacob brock_fuzzy_69

Link to comment
Share on other sites

hahaha i got the bike used over a year ago and i put the pipes on right after i got it. and i have had the 200s in the entire time and it acturaly ran extreamly good.(but low end kinda sucked) i beat all my friends in races and you all will think im making this up because my jetting was off but i ran away from other banshees with the same setup (top end) so i never bothered to rejet it. i just rebuilt it about a month ago the old pistons and and cylinder walls were in very good shape it was actualy a waste to rebilid it at that time but i alreay had it apart. who knows maybe if i had rejetted it it would of been faster? :shrugani:

Link to comment
Share on other sites

My buddy had the same thing happen to him. He bought the quad off this kid who put sst pipes on it a 2 years before my friend bought it it ran great even when my friend had it.:whoa: Then I told him to get a k&n then I showed him how to rejet and I was shocked to see 200 mains in there. Funny thing is it ran the same with the 290s.Hes all set now with jetting but in despreate need for a rebuild with 80 psi in one side and 110 in the other. Hes the type of guy who rides and dosen t care. :shrugani: Sad to see it go to waist.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...