Straight plug engines are better than angle plug engines

[superherg]

bingo! i was wondering the same thing cuz strait plugs are the norm great post! hey any one know where i can find a RED springer seat saw one on the pirate sight but outta stock and bout impossible to talk to any one there

 

[sportscarpat]

Just fired up a brand new Grubee slant head yesterday. Runs nice and smooth compared to my previous Grubee slant head. I know, the carb is the reason, right? I don't think so as the carb is from the previous engine and I didn't change a thing on it. Maybe this newer production Grubee slant has lower compression.

 

[mapbike]

Just fired up a brand new Grubee slant head yesterday. Runs nice and smooth compared to my previous Grubee slant head. I know, the carb is the reason, right? I don't think so as the carb is from the previous engine and I didn't change a thing on it. Maybe this newer production Grubee slant has lower compression.

Or maybe it's just an overall better balanced engine....

The slant H. engine I have on my Karaoke is a very smooth running engine compared to the straight plug H. engine I put a slant head on, I also milled the slant head down quite a bit to increase the compression even more than it would have been with just the stock configuration of the heads sealing surface, this is where it seems I messed up, because that engine developed a huge amount of vibration after doing that mod.

I plan to work the straight plug head down just a tad and then use it back on the engine I took it off of, it should be back to good after that or at least that is my hope.

Peace, Shan

 

[Saddletramp1200]

I took putty and put on top of a piston then lowered it down to see how much I could mill the head to raise compression. Same gas less room, more bang. Not enough to even bother with. They are what they are. Expansion chamber will raise the band, but gearing is the key

 

[brett7777]

A question: I want more clearance for my 48cc. It's been suggested that changing the straight head to a slant head might cause the piston to hit the head?
Has anyone come across this?
I would like to change the straight head to something like this:
Bicycle Motor Engine Cylinder Head Cover 48cc Parts - Motorized Bike Cylinder Head Cover 48cc Parts - Bike Motor Cylinder Head Cover 48cc Parts - Motorized Bike Parts

 

[DuctTapedGoat]

Do you want more clearance, or do you need more clearance?

Personally, I would recommend using a slant only if you NEED more clearance. If the piston does in fact hit the head, use two head gaskets.