Angle Fire Head

GoldenMotor.com

MRJOHN

Member
Oct 31, 2009
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usa

bairdco

a guy who makes cool bikes
Aug 18, 2009
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living the dream in southern california
the slant head is just for frames that need more clearance for the spark plug. performance-wise, the design is lousy, and they're prone to warpage.

the links above claim that it has a better squish band, but i doubt it.

i have a Grubee GT-5 with the slant, and my 3 Grubee GT-4's with the flat head run circles around it. and they've all had the same basic mods.

i know people are gonna chime in and say how awesome their's are, but unless someone has any substantial proof other than "seat of the pants" wishful thinking i wouldn't waste my money if i were you.

i think they're ugly, too.
 

noco

New Member
Sep 9, 2009
343
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fort collins colorado
i second bairdco.....my flying horse center fire is faster than my grubee angle fire....weird the cheep one being fastest...it kills the grubee on the low end and pulls away at the high end
 

tintor

New Member
Oct 7, 2009
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Tulare,calif
That is the way it seems to happen..I have done mods in the past to find out the stock way is better. you also have to remember that they spend a lot of $ to market best product
 

Russell

Well-Known Member
Apr 19, 2009
1,276
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MA
i second bairdco.....my flying horse center fire is faster than my grubee angle fire....weird the cheep one being fastest...it kills the grubee on the low end and pulls away at the high end
Sounds like you have the perfect setup to put this question to bed. If you could swap heads on the two engines and post the results. Otherwise there are so many variables from engine to engine even from the same Mfg. That you don't really know without a swap using two motors that you know well.
 

noco

New Member
Sep 9, 2009
343
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fort collins colorado
cant swap heads... the center fire will not fit the other bike.... like it was said the slant head is for mounting issues... id like to hear from someone who could try it though... it could end this debate... believe me id like to swap the heads
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
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living the dream in southern california
i think i could swap the heads on my bikes. the only difference is the GT4 has 6mm studs and the GT5 has 8mm. but the holes on the GT4 are larger than 6mm anyways, so it should fit on, and it'd only take me 5 minutes to swap 'em.

i keep thinking about doing it, but i just haven't really cared enough to bother.

i'll try to get around to it one of these days...
 

noco

New Member
Sep 9, 2009
343
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fort collins colorado
thats why we are just swapping heads...both of us have motors where the centerfire is faster....now if we switch the heads we should be able to isolate wether it is the motor or the head that is causing the speed difference
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
264
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living the dream in southern california
bobby, get the GT4. i have 3 of them and one GT5, and i built another for a friend. my GT4's have more power and run circles around the GT5's.

all the motors get the same clean-up treatment, porting the intake manifold and exhaust, cleaning up the transfer ports, decking the head, etc, and the GT5's i've run just don't have the same power as the GT4's.

as long as i can still find them, all the motors i buy from now on will be GT4's.