Jump to content

Question about porting.


Recommended Posts

So i really want to start building me a dune/play bike.

I have a few questions about porting.

 

 

I was reading on wildcard that it says he will match your case ports and stuff :confused:

ALso Im on a stock crank stock bore. Do i need to bore it?

Can i just buy a set of jugs ported and put them on my bike, what do i have to do to the bike, will the cylinders fit good with the port or what exactly is boring.

 

What do i have to do to port the bike, Sry i have never ported my bike so i dont knwo what im doing. Thanks.

 

Joe

Link to comment
Share on other sites

So i really want to start building me a dune/play bike.

I have a few questions about porting.

 

 

I was reading on wildcard that it says he will match your case ports and stuff :confused:

ALso Im on a stock crank stock bore. Do i need to bore it?

Can i just buy a set of jugs ported and put them on my bike, what do i have to do to the bike, will the cylinders fit good with the port or what exactly is boring.

 

What do i have to do to port the bike, Sry i have never ported my bike so i dont knwo what im doing. Thanks.

 

Joe

 

#1. Boring is when they make the cylinders larger. They go the minimum amount to make the cylinder true (same diameter at the top and at the bottom) This will require a new set of pistons because the hole is larger in diameter, so you need a larger piston. Most shops prefer to do a bore job after they port a pair of cylinders. That way the bore is 100% fresh and true.

 

#2. Porting is when they smooth the ports in the cylinders. It allows air to flow better. They also opean up the ports in the sleeves. That changes when the fresh fuel and air come in and when the exhaust goes out. It is like putting a performance camshaft in a 4 stroke engine. It is highly recomended that if you dont know what your doing to have some one do it for you. You can ruin a good set of cylinders pretty fast.

 

#3 Port matching the top case half to the cylinders is when they opean up the side of the case a little bit so it is an even flow of fuel and air from the crank case up in to the transfer ports. (ports on the sides of the cylinders)

 

#4 You can get a pair of cylinders already ported and they will go on your banshee's engine fine. I would highly recomend sending them to some one and have them checked out first. That way if they need bored they can do it. Other wise you risk having a bad running engine due to low compression, or worse yet destroying the cylinders, and crank because the piston skirt broke. When the cylinders get worn they become to large for the pistons. They pistons can rock back and fourth in the cylinder and that is what brakes the bottom of the pistons off.

 

#5 You could also buy a pair of non ported cylinders and send them to a builder. That way you dont have to tear your banshee down and wait. Brandon at Wild Card probably has a pretty quick trun around time. So it wouldnt be any big deal to send him the whole engine. That way all the engine assembly would be done. Other places my take longer to do the work. The more popular the builder the longer the wait.

 

josh

Link to comment
Share on other sites

Depending on the condition of the bore, you may just need a hone job to clean the cylinder walls for the new piston rings to seat properly. There are some other things to consider along with a port job to get the most performance out of the build. Such as what type of exhaust, intake, bottom end mods and timing to run. Any good builder will want to know things about your riding style, elevation, fuel you plan on running and your weight. They will make recommendations for supporting mods to get you what you want out of the motor. What are your current mods?

Link to comment
Share on other sites

My current mods are

 

Toomey t-5's

K&N filter

 

 

I have a timign plate

Have a cool head

(had to uninstall these do to a stock calss at the drag event i wanted to run. I will be runnign ether 18 or 19 cc domes

 

 

I want to do a aggressive drag port but still be able to have a little low end to trail ride once a month.

I will upgrade to the following stuff depeding on what the builder tells me

 

Carbs

Pods

+4 swinger

ASk them what gearing they would suggest

Shift star mod.

trued/weld stock crank

Vf3s

CPI Inframe pipes

Edited by TurningRPMS
Link to comment
Share on other sites

Your altitude and fuel considerations will determine the dome size that is best suited for you. Depending how fast or technical the trails you ride will be the deciding fator on how aggressive of porting to go with and what type of pipes to run. The T-5's are a great all around midrange pipe and can be adapted well to a dune or trail environment or both if the builder knows what he is doing. I really like the performance of the CPI's for a dune motor and they can be made quite manageable on faster trails aswell. As for the reeds I suggest a set of dual stage reeds and ported stock cages, these will perform very close to the V-Foce on a stock cylinder setup and for less than half the cost. The stock carbs are highly under-rated and can be pushed into the 70hp range, but a nice set of flatslides would be a great addition at a later date. True and weld the stock crank is highly recommended to prevent a crank failure especially when increasing the compression and hit of the engine. The pods are good for more air flow if it's not muddy/wet where you ride. If the trails are faster then a plus 4 arm would be fine, but if the trails are tighter and more technical I wouldn't recommend a setup requireing more than a plus 2.

Link to comment
Share on other sites

I run a Dune Ported 4mill with CPI's. It works good for the trails that I ride. From the sounds of it they are tighter trails than what you run. I wouldnt go with a full drag port. I had a 4 mill drag ported with cpi's and the same modds in my sig. It pulled like hell on the extreem topend. It just wasnt fun riding on the trials.

 

If you got the cash while you have your engine appart there isnt a better time to do a 4 mill. :biggrin:

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...