What Head To Run

[David wulf]

78 thousands with a piece of floor tile and some sandpaper? Yikes! I thought you had access to some machinery? I can't say that too many folks here, if anyone here for that matter, would recommend this!

Bryan, if you need the head milled, find a local machine shop! Nearly impossible to to get a square cut off the floor!

I do have access to a mill but I have done them this way and it works for me .
If you had a clue to what you are talking about , I didn't say floor tile , I said a piece of marble which are cut true . A piece of glass would do the same thing . Whatever this works for me I guess because I know what I'am doing , but don't say it can't be done and come out true .

 

[CarPlayLB]

M'bad! I just re read your post. Here is the quote "How I mill is I sand the head , I have a marble tile from Home Depot " You are correct. It does not say floor tile. I guess we can "assume" that you meant counter top tile, but here in Cali, marble countertops are usually one piece, not tiles. Oh, marble for the walls in the shower? that IS different than the floor tiles, which are vastly different from the countertop tiles. Home Depot is known for the highest quality "flat" marble tiles around!
You are good at that "cause you know what your doing". You just suggested that Bryan follow your lead and go to Home Depot. I guess you AND Bryan are good at this. I don't know Bryan's skills like you. Again, my apologies. Right now, Danny01 is on his way to Home Depot because now HE thinks that is a great idea. I hope he does not sand in one direction, or put too much pressure on one side and not another. He may do it dry to save money on WD40.
I am in awe of the knowledge and this is inspiring me to grow and learn how to do things. Thank you for the clarity on this.

sorry ...gotta go stretch

 

[David wulf]

M'bad! I just re read your post. Here is the quote "How I mill is I sand the head , I have a marble tile from Home Depot " You are correct. It does not say floor tile. I guess we can "assume" that you meant counter top tile, but here in Cali, marble countertops are usually one piece, not tiles. Oh, marble for the walls in the shower? that IS different than the floor tiles, which are vastly different from the countertop tiles. Home Depot is known for the highest quality "flat" marble tiles around!
You are good at that "cause you know what your doing". You just suggested that Bryan follow your lead and go to Home Depot. I guess you AND Bryan are good at this. I don't know Bryan's skills like you. Again, my apologies. Right now, Danny01 is on his way to Home Depot because now HE thinks that is a great idea. I hope he does not sand in one direction, or put too much pressure on one side and not another. He may do it dry to save money on WD40.
I am in awe of the knowledge and this is inspiring me to grow and learn how to do things. Thank you for the clarity on this.

sorry ...gotta go stretch

You feel better now !!!!! Lol

 

[CarPlayLB]

You feel better now !!!!! Lol

nope! Still stretching. I need to get the feel of patting my own back! just went to the Home Depot website. Here is how they described the tile
"first-quality natural marble tile for floor, wall and countertop use"...hahaha...I nailed it! Right?

now, please tell us how well you know Bryan and his skillset, so we can understand your statements.

 

[David wulf]

nope! Still stretching. I need to get the feel of patting my own back! just went to the Home Depot website. Here is how they described the tile
"first-quality natural marble tile for floor, wall and countertop use"...hahaha...I nailed it! Right?

now, please tell us how well you know Bryan and his skillset, so we can understand your statements.

Merry Christmas

 

[delray]

bryan

Would I benefit anything by drilling the head for 5.5 valves? Or just run the stock ones

if you are just looking to put it on a minibike and just have some extra power and not looking to drag race it in a 1/8 or 1/4
just use the stock size valves.
if you do go with that after market cam. i would replace the factory valves with the ss valves and automotive style retainers and keepers/26# springs/moly pushrods/guide plates and correct porting.
then your top end parts can sing to the moon..........

 

[Bonanza Bryan]

bryan
if you are just looking to put it on a minibike and just have some extra power and not looking to drag race it in a 1/8 or 1/4
just use the stock size valves.
if you do go with that after market cam. i would replace the factory valves with the ss valves and automotive style retainers and keepers/26# springs/moly pushrods/guide plates and correct porting.
then your top end parts can sing to the moon..........

That was the plan! And to my surprise the engine came stock with automotive style retainers. Thanks for the insight time to order some parts!

 

[delray]

your going have fun with it. when you get it glue together bryan.........:thumbsup:

 

[Bonanza Bryan]

This will be a build to keep your eyes on:drool:

 

[OND]

Good luck on the build Bryan...I'm subscribed ...:thumbsup:

 

[DBMonster85]

I think the head you have is plenty for the build you are doing. That head will support some nice power. Spending the cash on another head at this point is a waist. You could use that money for other things in your build. (Like safety parts) all and all I would port and mill that head get that black mamba and 26# springs with the 22mm Mikuni rod and flywheel of course and your bike will be doing well on a low budget. Jmo.

 

[Bonanza Bryan]

Ok guys have a few more questions. How much should I get take. Off the head? I've heard anywhere from .050 to .075. I'm going to be running a flat top piston and a +.020 rod. My piston is .040 in the hole stock. Also what about push rods? Since I'm going to be shaving the head do I need shorter pushrods or will stock length pushrods be fine? I'll be running 1.3 ratio rockers

 

[delray]

bryan, your making it to hard on your self. if your going to just use the engine for riding around on your minibike? i personally would only go .050 on the head and black mamba cam and stay with the 1.1 rockers(maybe if the money allows, go with rollers) now if i am right that cam has a .275 lift? if you add 1.3 rockers that puts you way over .300+ lift. i personally don't see how your setup will benefit the way your engine his setup and for what use your going to use it for. also you may start to run into valve to piston clearance problems? wait until you mill that head and have it installed on top of that flat top piston and you still have to pull it over with the rope. not impossible to still pull it,but you will feel it and you will really feel it when it kicks back on you...
if you do go with a 22mm Mikuni, i would have at least a 120 jet to start out and a 12.5 pilot(stock) you may have to go with a 15 pilot,but you won't know until you have it running. also you might be bumping the jet higher. for example 122.5 or higher(look at the plug,it will tell you what to do)
also one other thing when you have that engine running. you can forget about trying to idle around at very low speeds. your going to find out that it's going be on it or off it. but its alot of fun cracking the throttle wide open...........

patent pending intake......

 

[Bonanza Bryan]

I figured I could always run a thicker head gasket if needed. The Pistons in the hole .040 if I add the .020 rod that'll still put me .020 in the hole with the thinnest headgasket still puts me around .030 piston to valve clearance. Which is what I hear is what is acceptable. So I'm pretty confident with running that just trying to figure out my valve train. I think I'll run stock rockers and see how those work out. Just still wondering about the pushrods length with a .050 milled head? Stock length or shorter ones?

 

[Newoldstock]

b

patent pending intake......

Wow that intake is very very trick.
I like that so much I am going to violate your patent.
I made one that was very close in fuction but my filter curved in 45 from the intake.
Yours is much slicker

http://www.oldminibikes.com/forum/avatars/oldschool?dateline=1279303613

 

[ole4]

"I figured I could always run a thicker head gasket if needed. The Pistons in the hole .040 if I add the .020 rod that'll still put me .020 in the hole with the thinnest headgasket still puts me around .030 piston to valve clearance"


head clearance has nothing to do with valve clearance. Milling the head does not change the clearance from piston at TDC to the head. .030 is a safe minimum so .020 in the whole +.010 head gasket is OK. Milling the head does affect valve to piston clearance but again with a black mamba and stock rockers there would be no problem and even with 1.3 rockers you would be OK but due diligence you should check just the same. FYI duration and lobe centers has more to do with valve clearance than lift.

 

[kruger]

So glad I found this thread, I have a clone motor with stock crankshaft, arc standard length rod, a bsp3 cam , & flat top Honda piston. I was 0.00 in the hole , question is with my 14cc head is my compression too high ? I used a stock Honda gasket & I broke my crankshaft. I have the new 18cc head that came on motor, which head should I use for best power ,rpm ,&reliability ?

 

[Prowler08]

No such thing as too high of compression!!! lol
Depends on what fuel you want to run...

Assuming you are 0 in the hole and only used a .009'gasket no wonder you had bad things happen...
You would need to stack 3 .009 gaskets to be safe...

A stock for stock 14 or 18cc head... The 14 will give you more compression, so a little better than the 18cc, but if you modify the 18cc it is a better head than the 14cc...

Either head in stock form flow the same...

 

[Jrdragbike]

I have a head forsale
Its ported milled and it has 28.5/25 valves. It was on a cruiser that turned 10,000 all the time

 

[ole4]

In the post that quotes NR racing there were a number of things that do not add up.
1) It is important to know that actual flow through the head is also a function of valve lift. Needless to say, the more lift, the more flow. (Note: higher lifts can decrease velocity, which in turn decreases torque

How does more lift and more flow reduce port velocity?

2) For high RPM operation (with big carbs & cams) the 27.5 mm intake valve will help and will allow 20 hp. We have tested 28.5 & larger valves but have not seen any improvement.

Again makes no sense unless you are putting a 28.5 valve of a stock seat and leaving the ID to small or the minimum cross section of the port is too small.

3) A good three-angle valve job will allow up to 15% improvement in flow on a GX160/200 head

Only if the original seat was a single 45 degree angle but every Honda or clone head I have seen have all had 3 angle valve jobs. Also it affects mainly low lift flow. The larger intakes improve low lift flow a lot more as when the valve is just starting to open there is a lot more area for air to flow thru. Basically up to .18x valve diameter flow is not restricted by the port but is controlled by the seat and valve angles and valve size.