Page 1 of 3

Scoot RS 'Atomic' reed valve conversion...

Posted: Fri Aug 10, 2012 8:27 am
by drunkmunkey6969

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Fri Aug 10, 2012 8:54 am
by Andy Pickering
If anyone would Martin would i should imagine Dan..give him a bell..

So did these ever actually ever see the light of day ? After Randals rants we never got an answer on these and not heard of anyone using one at all..lth and mbd reedvalves have been well received and seem to have erradicated the dreaded spit back and improved fuel economy..one negative i remember was the use of the rdlc parts as people have been critical..

Sent from my GT-I9000 using Tapatalk 2

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sat Aug 11, 2012 8:37 am
by tavspeed
thers a thread on the lcgb about them,general opinion is there is a lot of finnage to remove,not a good idea on a lambretta.

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sat Aug 11, 2012 9:35 am
by shocky
tavspeed wrote:thers a thread on the lcgb about them,general opinion is there is a lot of finnage to remove,not a good idea on a lambretta.
yes it looks like you do altho i see there being somewhat economical with the truth and "shave" is the word they use :lol:

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sat Aug 11, 2012 11:45 am
by camel
drunkmunkey6969 wrote:Anyone in UK stocking these?

http://scootrs.com/moreinfo.cfm?Product ... urrency=UK
good question Dan,been thinking on the same lines.i think they look a great bit of kit,i too would be interested in buying one if the price is good compared with the other ones on the market.

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sun Aug 12, 2012 12:56 am
by RAP 200
I run a 6 pettal yz yamaha reed manifold on my rapido 240, the spec is, JS440 71mm weisco piston, 10.5 to 1 comp ratio,34mm vm mikuni,jl4, variatronic, mec crank with rd400 con rod, i have cut 2x extra transfers up from the inlet,port timings are exhaust 187 deg, transfer 132 deg, boost ports 130 deg, now my reed manifold in much larger than the scoot rs one to fit the Xer reed block ,i had to remove more alloy off the fins than the scoot rs diagram, [down to one of the barrel studs],i have never had any trouble with overheating, and i live in south Australia and our summer temps can be between 35 to 45 deg celcius, my take on it is you are remov ing thin fins and replacing it with a large chunk of alloy on the coolest side of the cylinder.

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sun Aug 12, 2012 8:57 am
by coaster
RAP 200 wrote:I run a 6 pettal yz yamaha reed manifold on my rapido 240, the spec is, JS440 71mm weisco piston, 10.5 to 1 comp ratio,34mm vm mikuni,jl4, variatronic, mec crank with rd400 con rod, i have cut 2x extra transfers up from the inlet,port timings are exhaust 187 deg, transfer 132 deg, boost ports 130 deg, now my reed manifold in much larger than the scoot rs one to fit the Xer reed block ,i had to remove more alloy off the fins than the scoot rs diagram, [down to one of the barrel studs],i have never had any trouble with overheating, and i live in south Australia and our summer temps can be between 35 to 45 deg celcius, my take on it is you are remov ing thin fins and replacing it with a large chunk of alloy on the coolest side of the cylinder.
If you look at the pictures on the Scootrs site it looks like around 20%-30% of the fins have been 'shaved' off. The LTH manifold does not need ANY fins removing and the MB 'shorty' manifold that I have only affected 3 fins, largish chunk out of one and smaller chunk out of the second and a small piece out of the third. It's short enough to allow the fitting of a filter under the panel and is available with a 6 petal reed block. Niether the LTH or MB manifolds are big enough to house the Yam reed block but why would they need to be? Is it realistic to expect to be able to port a piston ported barrel sufficiently to flow enough air to justify it? Even a standard spec TS1 would flow more air.

As regards the cooling effect of a large lump of ally rather than fins, the fins are cooled by the forced air within the cowling and will disipate heat from all round the cylinder, not just from the imediate area. I would say that the manifold will be insulated from the barrel to some extent by the inlet gasket and not be anywhere near as effective as the fins removed. You don't state what sort of riding you do or if your bike is full bodied or not but I would personally be extremely concerned about the loss of cooling on long sustained (50-60 miles) runs. That last point would be born out by the number of WC conversions and the INCREASED fin area on the new Avanti kit :?

Just my humble uneducated opinions and as ever, always happy to be corrected.

Here's some pics of the fitting of my MB manifold:
Image

Image

Image

Image

Image

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sun Aug 12, 2012 12:35 pm
by camel
give it a fair chance....too many assumptions as per usual.facts are what we want!

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sun Aug 12, 2012 2:17 pm
by coaster
camel wrote:give it a fair chance....too many assumptions as per usual.facts are what we want!
Strange attitude fella :? I thought this forum was all about debate and sharing of knowledge/experience/opinions. If you would like to buy one, grind most of your fins off and report back please feel free :fb:

Re: Scoot RS 'Atomic' reed valve conversion...

Posted: Sun Aug 12, 2012 2:35 pm
by Darrell Taylor
The base and rear of the cylinder around the inlet are areas cooled well by the continual supply of coolant in the form of fuel/oil and air travelling through the inlet around the case and up the transfer ducts as well as the additional boost port/s cut in ,the emphasis is on cooling the head and the top of the cylinder where the heat is generated ,the fin removal more or less wont make too big a differance but on air cooled motors you can never have enough to keep the cylinder and head thermally stable to withstand power losses,so good to keep as many fins as possible but in that area youd not notice/feel a differance