'81 G5 & SP 1000 Intake Manifolds

[Groover]

Does anyone know if the L & R manifolds are interchangeable on the 81 G5 (same as SP1000 from what I understand). The parts manual for the G5 does not show this style. It shows the solid mount intake manifolds used on the square slide type carbs. I can only seem to find the replacement for the LH, but no RH for this style. For more mystery, the RH one on mine does not have a part number printed on it and it just does not seem to exist according to the world wide web..... If I were to get 2 Left Hand ones, will it work for both sides? Also, what is that metal nipple for?

Here is what they look like:

Left Side (LH)


Right Side (RH)


Thanks for the assistance.




 

[fotoguzzi]

pretty sure those are not stock, never seen them attached with a hose clamp at the motor side.. kinda spendy but these are what you need.
http://www.mgcycle.com/product_info.php?products_id=178

[Antietam Classic Cycle]

Left and right do have a slightly different bend and overall length. If you're running pod filters, it probably wouldn't hurt to run two of one side. If you still have the o.e. airbox, the angle will be off.

You could always replace them with Delrin manifolds: http://www.mgcycle.com/product_info.php?products_id=178



Or metal manifolds and rubber sleeves as on other Guzzis.

I think the metal pin is removed and a nipple inserted for carb balancing.  

[Groover]

Thanks guys. From what I understand (called Harper too) these are stock Moto Guzzi intake manifolds, but mostly used on the SP model and apparently on later model G5's. The part number for the LH is 17116265, and is available at a few places. I currently still have the stock filter setup, but I want to change things I think. My air filter box is all cracked, and no longer meets the solid tube/housing (where the air filter goes) plus it just seems like the stock filter is impossible to get to and makes changing the LH condenser also a pain too.

So I'm really confused on what I need exactly to upgrade/fix my intake setup as it seems there are a bunch of things that seem close but not quite. I also asked Harper about the K&N filter and apparently the single one (with the two connections, but one filter) will not fit the SP style intake (like mine) so I would need to get the 2 individuals for $90-ish... then I have to figure something out in regards to the crankcase venting as well.

Any suggestions you guys may have would be great. I'm ideally trying to keep things somewhat stock, and I'm trying to avoid up jetting and things like that if they can be avoided. The bike, even thought the filter isn't quiet sealed perfectly to the stock air box, runs like a champ - I just rebuild the carbs and all seems to be nicely balanced.

The reason I'm looking for these rubber manifolds is that are showing some cracks and I can see them busting any day now...

Looks like my best options are those at MG cycle? I don't understand which filter I need to use if I go with those though... sounds like they are more straight?

Thanks again for the help.

[Antietam Classic Cycle]

Right side is 1711 6365. I have a pair of good used ones here somewhere. The rubber is quite thick, so the cracks probably aren't the whole way through.

Filters that will fit directly onto your PHF30s are the K&N RU-2450. Can be bought for $32.99 ea. on Amazon: http://www.amazon.com/RU-2450-Universal-Rubber-Filter/dp/B00062YQRA/ref=sr_1_1?ie=UTF8&qid=1407188789&sr=8-1&keywords=k%26n+ru-2450

The stock airbox does lend some support to the rear of the carbs, removing it may accelerate deterioration of the rubber manifolds. I've fabricated brackets that went from the frame to the rear of the carb to support the carbs after switching to pods and that seemed to work well.

The breather you'd need would be the "Le Mans" unit:



http://www.mgcycle.com/product_info.php?products_id=490

[dilligaf]

Your picture is what I have on my SP.  Mine cracked when I installed K & N air filters, most likely do to the lack of support that was provided by the stock air box.  The cracks appear to be mostly cosmetic however, I sealed them with a coating of RTV and support the intake side of the carburetors with a tie wrap attached to the frame.  So far, so good.

Also, what is that metal nipple for?  The metal nipples are removable plugs. You remove the plugs to  synchronize the carburetors.

I have been told   http://www.mgcycle.com/product_info.php?products_id=178 ,due to the angle, will cause the filter to interfere with the side covers. Would anyone know if the is correct?  :BEER:
Matt

[Antietam Classic Cycle]

I have been told   http://www.mgcycle.com/product_info.php?products_id=178 ,due to the angle, will cause the filter to interfere with the side covers. Would anyone know if the is correct?  :BEER:
Matt

Yes.

[fotoguzzi]

pretty sure those are not stock,

I stand corrected but my 81 Convert did not have those and why did they use 2 different intake manifolds? a few G5's have passed through my garage too and I've never seen those hose clamp connections on the engine side.

[handyandy]

Harper's had some repops 3 years ago.

[Groover]

Ok, thanks again guys. After reading the replies and suggestions, which I greatly appreciate, I decided to keep it all stock setup style; but still, what a challenge that can be. Thanks Antietam Classic (can I just call you ACC?...) for the part number for the right side which for some reason I could not locate anywhere. Once you posted the RH part number, it made me realize why I was fighting the carb/intake manifold installation this weekend; I have them on backwards (L & R swapped), so that's not helping those cracks much...

I was able to piece together two new intake manifolds after some crazy searching. I got the LH at Harpers, and the RH at Englandmoto. A little more than I was wanting to spend, but hopefully with good care and stock setup they'll last me years to come. I also picked up a new stock air box from MG Cycle... I'm just spreading the love (my hard earned money) to everyone out there! - I just wish they would all carry the same stuff and agree on pricing - trying to be frugal cost me a lot of time!

Thanks again for the assistance, and I hope this thread helps others looking for the same parts save some time by not having to hunt for them.

[Antietam Classic Cycle]

Thanks Antietam Classic (can I just call you ACC?...) for the part number for the right side which for some reason I could not locate anywhere. Once you posted the RH part number, it made me realize why I was fighting the carb/intake manifold installation this weekend; I have them on backwards (L & R swapped), so that's not helping those cracks much...

Call me Charlie.  :)

Actually, I had the numbers backwards: 1711 6265 is the right side and 1711 6365 is the left. The metal pin should face down.

[Groover]

Thanks Charlie. Good tip on the pins, I though they pointed up (that's how they were when I got the bike)

[blackcat]

Thanks Charlie. Good tip on the pins, I though they pointed up (that's how they were when I got the bike)

The pins pointed up on mine.

[Antietam Classic Cycle]

The pins pointed up on mine.

Hmm. Two websites (Harper's and Stein-Dinse) list 1711 6265 as the right side and if that's the case the pins would point down on the ones I have.  ???

Edit: It looks like they could be installed either way depending on which end is slipped onto the manifold. But, only one way is correct. Both of mine were slipped onto the manifold the wrong way. When installed correctly, the pin is up as blackcat says.

[dilligaf]

Mine are up.  Lot easer to sink the carburetors when you can see where to attach the sync tubes.  :BEER:
Matt

[handyandy]

I had to replace pins with screws. 1 little hic up and the will pop out.

[rodekyll]

I found barbed, rubber-ish tapered plugs that fit mine.  They were pointed down when I got the bike.  I thought it made it too hard to see if they were still there or not so I swapped l/r so's they'd be up.  The bike didn't care.  It was a pita trying to get the oem filter back on so I did pods and that tubby little breather box pictured above.

[Groover]

I'm posting this for those like me who miss some important details.... The engine side of the rubber intake manifold has a single groove (matches the single groove on the stubby aluminum manifold mounted to the head); The carb side has two grooves (and the carb has two grooves to match). I finally flipped my old/current rubber manifolds and they basically snapped right it - all is well.

In regards to the pins... are those screwed in or do the pop out like a plug?

[Groover]

Antietam Classic Cycle (Charlie) hooked me up with a nice set of used manifolds and they work great, nice and tight - Thanks again!

I also decided to keep the entire intake system stock, and I'm happy I did. Installed a new filter box, filter, new breather and drip hoses, and new breather valve. Now is all nicely sealed and sturdy just how Mr & Mrs Guzzi intended it to be  ;)

Thanks for the assistance on this and helping me make up my mind on how to go about this.

[Antietam Classic Cycle]

Here is what they look like:

Left Side (LH)


Right Side (RH)

Okay, now it's me looking for part of this setup.  I don't need the rubber elbows though, what i need is the aluminum flange that bolts to the head and the elbow slips onto. Anyone have a pair?

[Groover]

Charlie, I have the ones you sent me a year or so ago with the rubber elbows, but I only needed the elbows at the time. I need to dig them out, they're in my garage somewhere. PM with your mailing address (I think I have it, but just in case.) - I'll mail them to you once I find them and let you know when they are on their way. I'll look for them this evening, so good chance these will be on their way tomorrow.

[Antietam Classic Cycle]

Charlie, I have the ones you sent me a year or so ago with the rubber elbows, but I only needed the elbows at the time. I need to dig them out, they're in my garage somewhere. PM with your mailing address (I think I have it, but just in case.) - I'll mail them to you once I find them and let you know when they are on their way. I'll look for them this evening, so good chance these will be on their way tomorrow.

Super! I knew I had some at one time, but couldn't figure out what I did with them though. Thought they were just lost in my junque. ;-)

[Groover]

Charlie, I found them. They are boxed up now and will get them in the mail during my lunch break today. I'll PM with the tracking number a little later today.

[Antietam Classic Cycle]

Charlie, I found them. They are boxed up now and will get them in the mail during my lunch break today. I'll PM with the tracking number a little later today.

Thanks!

[Arizona Wayne]

At low rpms you can see those rubber elbows pulsate......like the motor is ALIVE !!!      

[centauro]

At low rpms you can see those rubber elbows pulsate......like the motor is ALIVE !!!      

And that " pulsating" action is what will gradually start tiny cracks in the rubber, which, when coupled with the carbs unsupported by the original air box setup, will accelerate their demise. So, they work well only with the original setup.
My 1984 SP had those same rubber manifolds, but the carbs were unsupported. The motor suffered from backfires and "sneezing" for years, which drove me insane, as, no matter what I did, I could never adjust the carbs to run properly. At one time, the sneezing actually blew the right carb off the manifold leaving it hanging by the cables and fuel line! I only realized that this behavior was all due to air intake leaks, and went away completely only after I modded the system with Delrin manifolds. Ran perfect ever since.

[Antietam Classic Cycle]

Well, the Delrin manifolds or original Cal II setup isn't going to work for me. In either case, the carb inlet would be pointed directly at my atf tank, leaving no room for an air filter.



If necessary, I plan to make some supports to help take some of the stress off of the rubber elbows.