Notched Cooling Fins?

Davezilla · Sep 30, 2015

The castor 927 is already mixed with an oil base so the amount in a teaspoon to a gallon wouldn't be very much, but you could mix it at 32 or 40:1 and be plenty safe.... you would want pure castor oil light the Sig brand stuff that's refined and de gummed if you want to add in with the opti2 or your favorite oil... this stuff is usually sold at hobby stores to mix in with model fuels, but here's an online source... it's kinda pricy, but 4 or 8 ounces would last thru several gallons of mix... http://www.sigmfg.com/cgi-bin/dpsmart.exe/IndexText/FSIGCO001.html?E+Sig

Davezilla · Sep 30, 2015

Yup... for the Fred heads, the only one at that price is the 6cc version... the specialty heads with dual plugs or different chamber sizes are all at regular prices, which are also very fair considering the quality and what you're getting.
Luckily, most everyday ridden bikes do really well on the 6cc version, which is why it's the most copied version of his heads and same for most the other aftermarket heads, the 6cc size will work on just about any setup. The larger and smaller combustion chamber heads definitely have their place, but for almost any street ridden engine, the 6cc is going to be the best choice....

Tyler6357 · Sep 30, 2015

Dave, thank you for sharing your knowledge! Do you think I will have to re-jet again when I put the FredHead on?

Davezilla · Oct 1, 2015

There is always a possibility since that head does make more compression you may need to go up a size, but with its considerably higher cooling capacity it will most likely balance out, just monitor your temperature and do a plug chop to be sure. The extra compression may mean you will need to run higher octane fuel so if you think you hear any pinging or see any signs of aluminum flecks on your spark plug when you check it, go up to premium and everything should be good.
Personally I haven't had any detonation issues with a 6cc head but I've been running 93 octane mixed with opti2, mine may ping on regular 87 octane pump gas on a hot day but I'm not going to chance it when it's running so good as is...

Tyler6357 · Oct 1, 2015

Dave--Awesome!....you have really helped!!

KCvale · Oct 1, 2015

mogollonmonster said:
They notch cooling fins on Harleys and most all big bikes I know of...

And well come to think of it, it would look neat, especially on a painted jug.
What does everyone think?

Hi Fellow ZOnie.
How about our AZ Card's ehh?
3-0 with a 2 game lead in our division.

Anyway, slots in your cylinder fins won't hurt anything nor will they help any.
The majority of heat dissipation is done via the head, which is regulated by the heat number on the spark plug.

I am no fan of high compression heads even for $40.
What I do is put in a bit longer NGK spark plug which adds a bit more compression itself and only $10, but you need to get the Heat Index Number right.

It works like this; the higher the middle number in the plug number, the more heat is dissipated from the engine.

The general rule is use the highest number you can run until it runs so cold you foul plugs, it's heat that burns the deposits out and your engine likes running plenty warm.

Heck, I even paint most heads with High Temp black paint which really hampers cooling, but I run NGK 5944 (BPR7HIX) Iridium spark plugs in all my 2-stroke builds for here in the valley even in summer with no heat issues.

This time of year you may need to warm up to a 6 just keep your engine hot enough to not foul the plug.

I hope that helps you understand how heat is transferred out and the importance of keeping some in.

Davezilla · Oct 2, 2015

If you can find a black paint that'll stay put and it's not as thick as engine paint, the black color really tends to sucked the heat toward the paint so it can actually aid in cooling... maybe see if someone in your area can anodize a few heads in black instead of using paint and see if it runs cooler... you could probably even polish the heads in a tumbler or vibratory shaker loaded with a fine media before having them anodized black for a really nice appearance when finished... the anodizing may not be cost effective if doing only one or 2 but if a batch of 10 or more was sent out it could help keep the price down...
I've seen one seller on ebay that sells anodized billet heads, they are all clones of the Fred, Jake's, BMW, and so on, I haven't seen any anodized stock heads available for sale tho... they do look cool in red,blue or gold tho....

mogollonmonster · Oct 2, 2015

WOOT GO CARDNIALS! Thanks KC, I've been wondering about plugs. Which brings me to the next question. How long can the threads on the plug be? The NGK plugs look a lot longer than my stock plugs, so I haven't bought one. I ordered a dozen plugs when I bought my kit, because I knew I'd have to do plug chops. What's the max thread count, before it hits the piston?

Davezilla · Oct 2, 2015

I'm not a fan of adding longer reach plugs on these to gain compression, but people have done it successfully and a longer plug can remove a few ccs from the total chamber volume. The problem is knowing how much clearance you got between the plug and piston crown, but this can be figured out by putting a small piece of clay or wax on the ground electrode of the plug then installing it and Gently bringing the piston up and over TDC, then pull the plug and check that the gap didn't move, then measure the thickness of the wax, clay,plastigauge, or whatever media used to measure the distance from the piston crown.
Since I don't use this method you will need to wait for KC to reply and see how much reach you can go with or how much piston to plug clearance is safe as well as effective.

mogollonmonster · Oct 3, 2015

I don't want to up compression, I just don't want the piston smacking the plug. The NGK plugs look longer than the ones I got from SD Stinger.

Davezilla · Oct 4, 2015

Here's a little cross referencing for ya.... http://motorbicycling.com/showthread.php?t=10560

dmb · Oct 4, 2015

i met carson palmer when he played at U.S.C. with my brothers son, nice guy back then. i'm sure he still is. funny thing is that troy polamalu was the softist talking player i ever seen, you would never know what a beast on the field he was if you didn't know him. it's good to see the card's doing good, looks like they got some stand up players. not unlike green bay.

KCvale · Oct 5, 2015

mogollonmonster said:
WOOT GO CARDNIALS!

I can't believe how bad we looked against the Rams, man they have a good defense.
One too many errors on offensive and pretty sad to loose by 2 points.

Thanks KC, I've been wondering about plugs. Which brings me to the next question.
How long can the threads on the plug be?

A stock plug is 12mm from washer to anode bottom.
An NGK is 16mm.
They won't work in a straight or milled head, but work just dandy in a stock slant head.

mogollonmonster · Oct 5, 2015

Dang, I can't use em. I've got a straight head... Any recommendations? I reckon I could take my plug into one of my local shops, and pray.

mogollonmonster · Oct 5, 2015

Damn Cardinals...

Davezilla · Oct 5, 2015

mogollonmonster said:
Dang, I can't use em. I've got a straight head... Any recommendations? I reckon I could take my plug into one of my local shops, and pray.

If you got a some what competent parts counter person you should be able to get them to match up the plug by comparing the size and reach, then you would want to know the heat ranges for that brand and from there it would be easy to replace the plug later or be able to cross reference that plug to get the brand and heat range you want.
I've found the Autolite #275 plugs work great in the Fred heads, but if I wanted to use a Champion plug for whatever reason, it would be easy to go online and find a site that has some cross reference charts to get the one I need from a different name brand like NGK etc...

crassius · Oct 6, 2015

mogollonmonster said:
Dang, I can't use em. I've got a straight head... Any recommendations? I reckon I could take my plug into one of my local shops, and pray.

I'd first try one with head loose & held down with my hand while turning crank to see if it hits (some chewing gum on top of piston will tell how close it gets if it seems to clear OK).

Davezilla · Oct 6, 2015

I've always used clay or wax for checking this, but chewing gum is a good idea... I use a piece of solder for checking piston to head clearance since it'll squish down without damaging anything but solder is too firm to use for spark plug clearance since it could bend the electrode and throw off the reading. One of those cheap digital calipers from harbor freight works really well for measuring the flattened sample.

KCvale · Oct 7, 2015

mogollonmonster said:
Dang, I can't use em. I've got a straight head... Any recommendations?.

Yep.
Get a stock slant head and NGK plug, ~$35 and you will feel the difference.

YesImLDS · Oct 7, 2015

KCvale said:
Yep.
Get a stock slant head and NGK plug, ~$35 and you will feel the difference.

Or a 6cc fred head and an NGK plug ~$45 and you will really feel a difference.

Notched Cooling Fins?

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