Author Topic: loop vs later intake manifolds  (Read 883 times)

Offline NoSprk

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loop vs later intake manifolds
« on: September 06, 2022, 06:08:08 PM »
so i was under the assumption that the difference between the loop frame and later intakes with sync ports is the actual neck the carb slides onto. i almost bought a set and we measured them figuring out they were 37mm vs the 35mm on the originals on the loop bikes (oops... for VHB29 carbs)

i found another seller with a set and was told that the difference isnt the neck diameter but the plastic spacer that goes over it. he said he can get a set of the sleeves that will make the later intakes work with my carbs.

does this make sense?
« Last Edit: September 06, 2022, 06:08:31 PM by NoSprk »

czakky82

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Re: loop vs later intake manifolds
« Reply #1 on: September 06, 2022, 07:01:29 PM »
I might have a set of the early plastic inserts. Shoot me a pm with you measurements if interested.

Online Antietam Classic Cycle

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Re: loop vs later intake manifolds
« Reply #2 on: September 06, 2022, 07:01:44 PM »
That is the difference. VHB29 (Loop) manifolds are 35 mm o.d. and 37 mm for later Guzzi with VHB30s. The i.d. is slightly different as well.

Yes, the 37 mm manifolds could be used with VHB29s if one swapped out the 35 x 40 sleeves for 37 x 40 sleeves. However, last I checked, there were no 37 x 40 (VHB30) sleeves available anywhere. I made a pair for a customer's G5 out of Delrin a few years ago, so that's an option.
« Last Edit: September 06, 2022, 07:03:51 PM by Antietam Classic Cycle »
Charlie

Offline NoSprk

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Re: loop vs later intake manifolds
« Reply #3 on: September 06, 2022, 07:09:59 PM »
oh ok that makes sense now except they look so thin right now I don't know how you could get any thinner of an adapter on there. the seller said he's going to look around and said he has a set of those adapters.

at this point I'm about to just say f-it and drill and tap mine. of course we would all like to have the OEM part if it's available and not a pain in the ass.

so does this look right as all the parts are there?






That is the difference. VHB29 (Loop) manifolds are 35 mm o.d. and 37 mm for later Guzzi with VHB30s. The i.d. is slightly different as well.

Yes, the 37 mm manifolds could be used with VHB29s if one swapped out the 35 x 40 sleeves for 37 x 40 sleeves. However, last I checked, there were no 37 x 40 (VHB30) sleeves available anywhere. I made a pair for a customer's G5 out of Delrin a few years ago, so that's an option.

Online Antietam Classic Cycle

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Re: loop vs later intake manifolds
« Reply #4 on: September 06, 2022, 08:08:03 PM »
oh ok that makes sense now except they look so thin right now I don't know how you could get any thinner of an adapter on there. the seller said he's going to look around and said he has a set of those adapters.

at this point I'm about to just say f-it and drill and tap mine. of course we would all like to have the OEM part if it's available and not a pain in the ass.

so does this look right as all the parts are there?





Yes. I just drill and tap.
https://www.thisoldtractor.com/moto_guzzi_loopframe_intake_manifold_modification_to_support_vacuum_balancing.html
Charlie

Offline moto-uno

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Re: loop vs later intake manifolds
« Reply #5 on: September 07, 2022, 01:03:15 AM »
  ^ +1 , I did the same thing .Peter

Offline guzziart

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Re: loop vs later intake manifolds
« Reply #6 on: September 08, 2022, 05:24:04 AM »
  ^ +1 , I did the same thing .Peter

Me too!
'72 CL350, '72 Eldo '87 LMIVSE, '91 CT70, '08 Wing, '23 v85 Travel


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