Are these front or rear intake manifolds?

[dontlikeoc]

I just found out that both front and rear intake manifolds have cracks that went all the way through to inside.

Are these from Parts'n more to go to the front of the carbs, or rear of the carbs?

https://www.partsnmore.com/cat_index...&category=carb

[dewibp]

The one label "carb holders" go on the front or bolt onto the head and then the carbs slide into them.

[tarzan]

The ones at PNM are intake manifolds and go between the carbs and heads.
The ones between the carbs and air cleaner are tubes to connect the two components.I have heard them referred to as velocity stacks too, but I think that might be a stretch.

[dontlikeoc]

Thanks for clarifying. So, as for the ones that go between the carbs and the air cleaner, where would you get them? i dont see anybody, including PNM and ebay, listing them. Is getting them from Yamaha the only way? The current ones are shrunk and dont barely connect from old age, I definately need new ones.

[dewibp]

I was just checking a couple sites for the air cleaner/carb boots but so far found none. I guess I've never heard, or seen, these shrink up to the point they are too short. Are you sure they are the right ones? They typically get hard with age and crack/become hard and difficult to install are the usual problems. Some one will be along to clear it all up for all.

[bikerphil]

You could just get another airbox from Andreas that has good stacks. JAT

[dontlikeoc]

The one on the #1 carb and air cleaner box is the iffiest barely covering the lip.

[cywelchjr]

Yep, mine are a bit hard to get connected on without them slipping off. I can get them there, but it's not easy. And yes I have the airbox positioned as far forward as I can get it to go.

[dewibp]

STILL thinking...... are you sure the air box is installed properly and not sitting too far back not allowing the boots to slip onto the carb inlets? If I remember correctly there is a way to "cheat" the air box (slide it back) so you don't have bloody knuckles and or a mental break down trying to get them all slid on. Check that the two bolts are in place on the side and the top do hickey is something or other............... brain dead now.

[dontlikeoc]

They have cracks that reach the inside. They are temporarily RTV'd. I will attempt fiddling better fitment.

BTW, are the carb holders(between the engine and the carbs) and air filter box joints(between the air box and the carbs) interchangeable with those for XS650 by chance?

[mxmikie]

http://www.xs11.com/forum/showthread.php?t=26136

[redbone]

you can get a little more travel out of the airbox movement by taking a rattail file [a small dremel grinder works even better] and filing out the mounting bracket holes in both directions . HTH

[DiverRay]

If they have been in the sun, they WILL shrink beyond the useful stage. Do as bikerphil has suggested and PM Andreas. You can also check with some of the closer owners, and see if anyone has a "spare" upper air box. The rubber parts ARE velocity stacks, and they DO help with the HP on these bikes. Yamaha did a very good job on the design in 1978.....

[dontlikeoc]

About getting a new airbox from Andreas, suggested by Phil, what does Phil mean by "good stacks"? Is he suggesting that this is more of the airbox issue? Better understanding would help me make the right decision.

[bikerphil]

Velocity stacks are the 4 rubber inlets that you are having problems with. There are a lot of extra air boxes out there just laying around because many people switch to pod filters.