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In the process of building a 70 mm bore TS & need to make a packer for additional clearance for the boost port.

Or do I? Does anybody have any strong feelings as to the effectiveness of the packing? I can only presume there is a benefit, but studying an MX barrel I have shows that the reed valve is well clear.

As for the packing, I have a choice of materials including alloy, tufnol (as previously used) & some hardish rubber/nitrile.

My main question, though, is to ask whether anybody knows the maximum thickness of any packing before there becomes an issue with frame clearance. All of the M6 fasteners (except the one that goes into the inlet) are now countersunk.

However, knowing the b@st@rd that these manifolds can be to seal, I have almost decided to add four M4 fasteners in each corner as the standard 'central' fasteners are a design flaw, IMHO. Has anybody else resorted to such measures?

TYIA for any advice

I've used up to 5mm packer, however had to re-shape the inlet this was with an R1 shock which is around 295 ish mm, so this dropped the front of the motor a little which aided it also, I now machine the reed valve and the inlet manifold taking around 2-2.5mm off each which effectively puts us back to square one, alternatively you could fit a casa off-set cone-bar, regarding sealing TS1 inlets, ye agree they can leak, however a small smear of Three bond sorts that out,

Thank you dscotty

The rear shock absorber is an aftermarket adjustable item (red spring. SPAX? Not Bitubo) so I am certain that it is longer than standard. I know for sure that it is adjustable on length.

(I don't much like having to rely on a sandwich of components sealed only by a proprietary compound such as Threebond, as I have had reed valve manifolds leak before after just a few miles, although Threebond [Yamabond] is an excellent product)

If I go the four corner fixing route, it will give peace of mind, though I could rout 'o' ring grooves as I will have to have the tool out for the packer to be made. I was really wondering if anybody had a sure-fire procedure that eliminated the need for relying on just the existing fixings.....

When you say "in my opinion" I think you're being too humble. It is a flaw. A 90 bend with no restraint is a weakness.

Nice to be humble though.

Apologies to hijack the tread but it is relevant,I have just purchased a MB manifold for my TS1,but it does not sit right on the cylinder,is it because I must use a packer with it ?

IMHO there are so many other factors to take into the equation... The manifold used, and offset cones... These are the factors for me that influenced the size of the packer I could use

Does it not depend on what reedvalve assembly being used, genuine Yamaha needs to sit taller requiring a5mm packer for boost port clearance and the remade Bgm version only requires a 3mm. I don’t use the paper gaskets supplied either and only use ThreeBond even though it’s a bit messy

Sorted it,you need the BGM Reed for it to fit a TS1

ROClarke wrote:Sorted it,you need the BGM Reed for it to fit a TS1

Did u get the Bgm stuffer as well ?

ULC Soulagent wrote:

ROClarke wrote:Sorted it,you need the BGM Reed for it to fit a TS1

Did u get the Bgm stuffer as well ?

Been curious off these reed stuffers.. ?
do you get any increase in performance using them?

ROClarke wrote:Sorted it,you need the BGM Reed for it to fit a TS1

I’ve used an MB manifold with standard TS1 reed with a 3mm packer and it sits fine.

Norrie Bodge wrote:

ULC Soulagent wrote:

ROClarke wrote:Sorted it,you need the BGM Reed for it to fit a TS1

Did u get the Bgm stuffer as well ?

Been curious off these reed stuffers.. ?
do you get any increase in performance using them?

Apparently they do but that’s open for debate. Think it directs the fuel charge more efficiently into the reedblock area but I’m sure one of our fine Racers would explain it in better detail

ULC Soulagent wrote:

ROClarke wrote:Sorted it,you need the BGM Reed for it to fit a TS1

Did u get the Bgm stuffer as well ?

No just the reed.
Any idea if there will be any difference in performance between this and the Imola manifold I am currently using where the reed sits inside it as opposed to inside the cylinder.

ROClarke wrote:

ULC Soulagent wrote:

ROClarke wrote:Sorted it,you need the BGM Reed for it to fit a TS1

Did u get the Bgm stuffer as well ?

No just the reed.
Any idea if there will be any difference in performance between this and the Imola manifold I am currently using where the reed sits inside it as opposed to inside the cylinder.

Don’t think there will be any difference in performance, only if the reedblock has been flowed will it make a tiny difference
Reed petals can make a huge difference depending on thickness and if there dual stage( Boyesen)

Further to the issue, the eventual solution, along with the packer that I made to suit:

Warkton Tornado No.1 wrote:Further to the issue, the eventual solution, along with the packer that I made to suit:

TS1 spaced out manifold additional fixings.jpg

IMG_1513.JPG

Is not a bit overkill in the screw department

Nice work, but a bit of threebond would've sealed it

ULC Soulagent wrote:

Warkton Tornado No.1 wrote:Further to the issue, the eventual solution, along with the packer that I made to suit:

TS1 spaced out manifold additional fixings.jpg

IMG_1513.JPG

Is not a bit overkill in the screw department

I didn't want to add additional screws after all the other engineering involved. With a packer increasing the number of faces to be sealed, this solved the issue.

dscscotty wrote:Nice work, but a bit of threebond would've sealed it

It didn't, nor did other similar products. In the end, this solution gave me peace of mind & saved time over all the attempts to seal requiring strip down, cleaning etc.

I've owned & worked on Lambrettas since 1973 & have worked principally in design engineering. The TS1 manifold would not require having to rely entirely upon a sealant if the fixings were four corner. It is a ridiculous design flaw.....

Nice. Correct solution.

The TS1 manifold would not require having to rely entirely upon a sealant if the fixings were four corner. It is a ridiculous design flaw.....

a 30 yr design flaw as well! Monza barrels only have 3 fixing points