50mm Big Bore Elite S Build

[dem0nk1d]

wouldn't hurt to open the intake ports up. looks *!

oh hail to the magic stick. =) Oh you want that spree tail light PM. Where to send the thing.

[bakaracer]

Your boost port needs to be ported more towards the crank more.you have a bottle neck going on so it would slow your flow coming to the boost port from the case.Don't forget to polish that exhaust port.leaving it rough will attract carbon buildup faster and create turbulance in the port which will disrupt the flow.you can also clean the transfers up and sharpen the spliters on the bore.helps to better the flow.other than that nice job on the build.

[Trafficjamz]

Your boost port needs to be ported more towards the crank more.you have a bottle neck going on so it would slow your flow coming to the boost port from the case.

Hmm ok I think I know what you mean. I don't want to cut too much.

Like this?



Top = the way it is now
Bottom = photoshop of your suggestion. (I wish it was as easy to cut, as it was to photoshop.)

[dem0nk1d]

you need to get some cartridge rolls and maybe even some polishing buffing pads. I need to get in touch with my buddy to chime in. He'll tell you what exactly to use. He's going to do the Port and Polish on my case.

[bakaracer]

Your boost port needs to be ported more towards the crank more.you have a bottle neck going on so it would slow your flow coming to the boost port from the case.

Hmm ok I think I know what you mean. I don't want to cut too much.

Like this?



Top = the way it is now
Bottom = photoshop of your suggestion. (I wish it was as easy to cut, as it was to photoshop.)

yup! that way the boost port gets the full charge.

[dem0nk1d]

Just got off the with my brother. He suggest using 100-120 grit cartridge rolls. This should get everything general smooth. Then to polish everything up, he uses these things that look like Red 3M Scotch-Brite hair ball. These things can hit all tight corners and what not. I'll get the link from him soon.

[Wheelman-111]

Greetings:

Funny things, ports. It can be very difficult to predict what effect changes, even subtle ones, will have on performance. All those pressure waves echoing around in there. You may improve flow volume but have a detrimental effect on velocity, which in turn affects charge timing and on and on... Maybe it works, but only at like 14,500 RPM?

Aside from his wealth of prior experience, Honda san can whip up 10 or 20 crankcases on which to spearmint with the last fraction of performance percentage. We only get one case at a time to try things, plus we're grafting a cylinder that's 25% or more bigger than Honda had in mind. May I suggest you proceed with due deliberation, and get all the advice you can before performing the surgery. It's harder to put material back.

[dem0nk1d]

http://www.ruffstuff.com/pages/finish.html
Cross buff

That's the Scotch-Brite thing i'm talking about.

[evilone]

Your boost port needs to be ported more towards the crank more.you have a bottle neck going on so it would slow your flow coming to the boost port from the case.

I've been told boost port should not go all the way down since you are reducing crankcase volume and the holes in piston skirt are there to allow flow to go up the boost port style Trafficjamz did. I was also told porting all the way down won't make a difference in performance and if anything you may get better performance. I trust Bakaracer and the performance cycle tech i deal with alot and both say port all the way. By the way, my boost port is all the way down and it runs great. I was restricted in rpm's using my R1 muffler so i got me a PG Long. In the spring i will find out results between mufflers since PG is a high rev pipe.

[evilone]

May I suggest you proceed with due deliberation, and get all the advice you can before performing the surgery. It's harder to put material back.

We need more responses! I posted a question awhile back about JB welds oil and fuel resistance. I never told why but i wanted to "put material back" so i would have less crankcase volume and the charge would go through the hole in piston and skirt instead. I've been looking for extra AF16 case halves (with no luck, i had a lead but still haven't heard from the guy) to try both ways of porting just to confirm and personally see if either way is better. I did add the material and am buying a new crank, i hope it's not a mistake adding the JB weld to my crankcase if results are no different. I don't need any chunks of the JB weld to fall off and kill my big bore


And finally...i posted on Forums Hawaii on which porting was the preferred method and both boost porting designs were recommended. The amount of material is really a small amount but i know it's a really small motor.

[bakaracer]

May I suggest you proceed with due deliberation, and get all the advice you can before performing the surgery. It's harder to put material back.

We need more responses! I posted a question awhile back about JB welds oil and fuel resistance. I never told why but i wanted to "put material back" so i would have less crankcase volume and the charge would go through the hole in piston and skirt instead. I've been looking for extra AF16 case halves (with no luck, i had a lead but still haven't heard from the guy) to try both ways of porting just to confirm and personally see if either way is better. I did add the material and am buying a new crank, i hope it's not a mistake adding the JB weld to my crankcase if results are no different. I don't need any chunks of the JB weld to fall off and kill my big bore


And finally...i posted on Forums Hawaii on which porting was the preferred method and both boost porting designs were recommended. The amount of material is really a small amount but i know it's a really small motor.

Some guys like the tapered boost port and some like the straight even amount all the way down.If you look at some dirt bike motors,there boost port is big and wide all the way to the crank and thats on the 60 and 65cc ones.I done alot of motors and tried both but got better results with the boost port matched to what the cylinder has all the way to the crank.

[Trafficjamz]

When are you going to put the crank in?Are you going with the stock crank or mini stroke(44.4mm)?

The plan, for now, is stock crank.
Plans can always change however. The main reason I have not started putting the crank back together is, lack of bearings gaskets and seals. That, and I still have some boost port work to do.

Where is the best place to get that stuff. And don't say "the honda dealer" cuz we don't got one

Go to babbits online.Thats where i ordered my stuff from unless someone has a cheaper place to order from.I don't go to the local dealer here because they charge there rate which is about 30% higher price.you should put the mini stroke crank in since you have it apart.With that bore you have its going to be fun to ride with that extra torque from the longer stroke.the mini stroke crank just drops right in.no case cutting needed.Get some honda bond to put the case together and goto schucks or napa and get gasket paper and make some gaskets for the base and reed cage.they sell the little thicker paper too.

OK bakaracer, you talked me in to it. I ordered my ministroke crank today!

[Trafficjamz]

My boost port is all the way to the bottom now. Right or wrong, its done.

[bakaracer]

That looks good.I like that you have a slight taper from top to bottom.If you get a mini stroke crank,get the one with the plastic insert.It helps with stuffing the crank area that is usually open and helps crank case pressure.don't forget to buy a oil plug to help withe the case pressure too.you will also have to get the aluminum base gasket spacer for your mini stroked 50mm bore.its to set the piston height correct.

[Spreetard]

don't forget to buy a oil plug to help withe the case pressure too.you will also have to get the aluminum base gasket spacer for your mini stroked 50mm bore.its to set the piston height correct.

from another post addressing both issues, written by trafficjamz himself.
from http://www.hondaspree.net/phpBB3/viewto ... =1&t=12728

I would think by having so much open volume behind the plug, you would loose a great deal of that needed crank case pressure. Genius yes, but ghetto fabulous for the win! I was always taught if you do something 1/2 a**ed then don't do it at all. Do it right the first time. Even if it takes a tad bit longer.

I 100% agree with you. Half * indeed. Silicone.... jb weld....what the F**k. Might as well have chewing gum and an old bottle cap.

Not to mention that an unmodified quarter does not even fit


If US currency MUST be used, This is the proper way to do it.
First of all, to deal with that extra space that the oil pump/plug takes up, I recomend Pennies.
Seventeen was the magic number for me.

And nobody likes dirty money....so I cleaned my money in the blast cabinet.

It is Important to have Clean pennies for the next step. Solder the pennies together


Next I measured the opening for the oil pump and then measured the diameter of a us quarter ( .030" over the size of the opening)


Four quarters with .030" off the edges (just beyond the ridges)

Now for the cover, a gold sacagawea dollar.
Drill a hole in the baby sacagawea baby's head as shown



All done .....and it only costs $2.17


See how it can swing out of the way just perfectly....best mod on my scooter yet!

Tune in next week when I will be making xtra base gaskets out of twenty dollar bills