Valve head

[2SlickNick]

I have been looking at the BBK and want to order a largrer (than stock) valve head and all that I see have this extra tab (on corner) on them.

Here is my valve head
http://www.buggymasters.com/forum/at...1&d=1383481037


This one has that extra tab
http://www.ebay.com/itm/SCOOTER-150C...item27d954e954


This one also has it.
http://www.sycpowersports.com/index....id=66&incid=29





This one DOES NOT have it ( oem maybe?)
http://knmparts.com/Cylinder-Head-w-...-GY6-150cc.htm


My question is will these larger valve heads work with my set up? Will that extra tab not matter as long as gasket seal is there? will 4 bolts still line up?

[Masteryota]

I don't think it will be a problem, it is likely put there for an bracket or accessory found on a scooter or other model engine, making it universal.

If you really want open that thing up, spring for the 4 valve head. Tom has the complete set up listed with all the goodies, but you would need to split the case to replace the timing chain. In this case, more is better.

[2SlickNick]

I saw where there is an additional bracket for scooters, hope that is the case. I would LOVE to order 4 valve head, but no case splitting yet until necessary, plus have to add longer timing chain , I believe. My birthday is coming up and my wife said her sister might by the valve head for me We will see. Until then just saving the money to get a quality one. either that or buy OEM and have it P&P. Leaning more towards the 58.5 valve head.

[351mustanger]

That looks like the egr provision. I would be concerned whether your cooling shrouds will fit with that head.

[2SlickNick]

ahhh very clever thinking. Cooling (plastic) shrouds forgot about those. Well I ordered cylinder head already and those air fins seem longer than stock, opps....
Maybe shrouds will still fit.

[2SlickNick]

at 2nd glance, I am optimistic both will still fit.

[Masteryota]

Originally Posted by 2SlickNick

I saw where there is an additional bracket for scooters, hope that is the case. I would LOVE to order 4 valve head, but no case splitting yet until necessary, plus have to add longer timing chain , I believe.

Complete kit

Until then just saving the money to get a quality one. either that or buy OEM and have it P&P. Leaning more towards the 58.5 valve head.

Either way would be good, but since you are in there, might as well go all out for a bit more $$, and get the big valve head and have tom port for you.

[2SlickNick]

True. Between 3 kids (one with special needs), wife, and saving for a newer house on a larger piece of property ( minimal 2 acres with woods close by). Every penny counts. It is so hard to make the wife understand the WORTH of the upgrades.
She says the buggy was running fine, then.... like always you take stuff apart and we don;t see it for a while.

This is only the first buggy. I plan on buying one just for her one day. What I buy her will be something needing work, so I can build it and customize it ( even if that means a pink buggy).

[2SlickNick]

58.5mm BB cylinder head arrived, with piston, boss pin, and gaskets.
looks nice. Only trouble I had was getting new rings into sleeve. I figured out it is easier to start inserting it on the work bench (just getting rings in past sleeve). Then with piston already in sleeve to just slip it over crank shaft and insert boss pin. Easy breezy. Now just waiting to order valve head, cam, and tensioner this weekend. Then I should be back in business to find appropriate jet size.

[mb1134]

The cooling shrouds will not fit over that head. I had to cut the tab off to put my shrouds back on. If you are going to spend the money on the Big Valve head you better have it P&P and shaved. Or you are wasting your money imo.

[Masteryota]

Originally Posted by 2SlickNick

58.5mm BB cylinder head arrived, with piston, boss pin, and gaskets.
looks nice. Only trouble I had was getting new rings into sleeve. I figured out it is easier to start inserting it on the work bench (just getting rings in past sleeve). Then with piston already in sleeve to just slip it over crank shaft and insert boss pin. Easy breezy. Now just waiting to order valve head, cam, and tensioner this weekend. Then I should be back in business to find appropriate jet size.

Most times it is easier this way, as long as you can still get the circlips in without dropping them in the case. Make sure they are seated correctly, or the wrist pin will destroy the cylinder.

[351mustanger]

I always take the old wrist pin and use it to push on the clips to make sure they are seated.

[2SlickNick]

So compared to a stock head, there is no difference with a larger valve head? Am I getting a 58.5 larger head simply because I got BB cylinder? Can't I just notch the cooling shroud instead of tab on valve head?
Clips are seated, thanks for tips.

[REAPER]

not for sure if this is what THE TAB IS or not but some are EGR heads and some are NON-EGR. I may be wrong but check in description and see what it says.

[2SlickNick]

Reaper I think you are right. I just wonder if my existing valve cover will still fit on those EGR heads. I will look around for a non egr head. Masteryota thinks it will be okay. Did you use same valve cover MB1134?

[REAPER]

I have been shopping around for parts for mine and recognized the pics, I just thought I would reply to offer my assistance, have had no luck finding performance parts for mine because they do not make any lol. But good luck on your build

[2SlickNick]

All of the larger valve heads have it, only oem ones don't...

[REAPER]

After looking at the head again your stock valve cover will not fit on that head, the EGR head and non EGR are designed different, good news is new valve cover on E-bay is only like 25 bucks. The EGR will just be mainly for looks seein as how the head you have pictured the EGR port is not drilled. Hope this helps

[2SlickNick]

http://www.scrappydogscooters.com/12...rformance.html
I did come across this 2/3 of the way down 59mm Big bore head I think this would work even with a 58.5 cylinder head huh...

[mb1134]

Originally Posted by 2SlickNick

http://www.scrappydogscooters.com/12...rformance.html
I did come across this 2/3 of the way down 59mm Big bore head I think this would work even with a 58.5 cylinder head huh...

Better off buying from Tom at SYC, as his is cheaper I believe. That is what I bought and yes my stock valve cover works fine with it. Only thing is it does not cover the extra tab on the EGR heads.

[mb1134]

Sorry, I thought you were talking about buying the big valve head from that website. The bigbore head is not the same as a big valve head and will not give you the gains a big valve would. You are better off getting Toms big valve head and having it P&P and shaved. That is the best bang for your buck. Period!

[351mustanger]

Just to clear up any confusion: you have a "cylinder" which is the bore that the piston is in, then you have a "cylinder head" which the valves are located in. I think most know what you are talking about but it can get confusing with the "cylinder head/valve head" names you are using.

[2SlickNick]

Originally Posted by 351mustanger

Just to clear up any confusion: you have a "cylinder" which is the bore that the piston is in, then you have a "cylinder head" which the valves are located in. I think most know what you are talking about but it can get confusing with the "cylinder head/valve head" names you are using.

Thanks for the clarification.

[2SlickNick]

What are your opions with stainless steel valves and 12,000 valve springs ?
Too stiff for 155cc?

[2SlickNick]

So, after reading some threads on here by Slestak. I have determined stainless steel lighter and more durable. 12,000 rpm valve springs not needed.

[Masteryota]

Originally Posted by 2SlickNick

So, after reading some threads on here by Slestak. I have determined stainless steel lighter and more durable. 12,000 rpm valve springs not needed.

Higher RPM springs are only needed if you are building a full out drag engine. The stainless valves are lighter, and generally flow better, but stainless is a bit on the soft side compared to the hardened valve seats, so you might need to adjust your valves a little more often than before as they settle in.

[SYCARMS]

Originally Posted by Masteryota

Higher RPM springs are only needed if you are building a full out drag engine. The stainless valves are lighter, and generally flow better, but stainless is a bit on the soft side compared to the hardened valve seats, so you might need to adjust your valves a little more often than before as they settle in.

I agree 100%. I do not run the stainless springs for they won't last as long, I still run steel. The only time you will need the HD valve springs is when you have a monster cam and you make power above 8000rpm. It amazes me how many advertise the HD springs as a necessity. Going with too heavy of a spring will ruin a head and naturally to light of a spring will ruin an engine. All these cams available for our buggies will work off the stock springs since they are considered mild cams. High lift cams with long duration and steep ramps will require the heavier springs. Most problems I have encountered out of stock springs occur when someone uses the no rev limit CDI thus over revving the engine to the extent of causing valve float. The stock CDI revs out at 7500-78-- rpm, most think by going with a no rev cdi they will increase the power or speed. The fact is even with a moderately built performance engine your power curve will not exceed 7800 rpm. Anything over that just waists the engine over time.

[2SlickNick]

okay, thanks for the clarification guys! I am mechanically inclined, but would be lost without this site. This site offers such an abundance of info and members willing to share knowledge that I could probably build a buggy from the chassis up.
Thanks everyone and thank you BUGGY Masters. Can't wait to get my ride running again.