Help with Intake manifolds

[gjones303]

Hey, I got some GL 1000 manifolds that are Chrome ones. I would like to put on an GL 1100 but I readed that the inside are different in size. How would this Affect the GL 1100 the way it Run Thanks

 

[OldWrench]

Interesting question and I really don’t know. But if the ports are smaller that will restrict the flow and possibly reduce the power a bit, it could also potentially affect the fuel air mixture but probably not by much. The only reason I say the fuel air may be affected is I know manifold design can have an affect on fuel delivery.

I suppose you have verified that the flanges will mate up perfectly with the 1100 heads. The 1100 intake flanges take a 40mm O-ring, I would make sure that the 1000 is the same.

I would think that if everything matches up worst case would be a slight power loss, but the 1100 seems to have plenty of power for normal riding.

 

[ekvh]

It might give some gains at higher rpm, but hurt the bottom end performance. The diameter of the runners affects how fast the air mixture is rushing in. Smaller, speeds the air up, bringing in more charge than bigger until you get way up in rpm. I would stick with stock sizes. I have even considered, but never got around to it, changing the 1100's 30mm and putting them on a 1000, 32 and 31 mm. Some day they will invent a material which can flex with the intake and adjust to desired responses. The 1200 intake runners 28mm are tiny compared to the 1100 and 1100. The Valkyries are even smaller at 24 mm. I believe the torque is better at bottom end.

 

[dan filipi]

Hmm, are you sure those intakes are from a 1000?
I thought they were the same inside, I know the 1200's are smaller.

Joedrum here on the forums has all 3 so he could verify.

 

[ekvh]

I have all three. They measure as the book says. I have a 77 which someone replaced with one 1100 intake runner. It smoothed out after getting the right one back on there.

 

[joedrum]

ive had it go both ways and inbetween the 1100 and 100 horns are a crude manufacture and are essentialy the same ...no payed to much attension to this part im guessing ....the biggest horns ive measured came off a 1100 parts bike i have 1980 ...so thats what i know

 

[gjones303]

Thanks Everbody

 

[RBG]

Also: Not all 100's are the same bore

venturi bore diameter 75 to 77 32 mm
78-79 31 mm
and 30 for the GL1100's

 

[slabghost]

As long as all are the same performance shouldn't be affected noticeably.