ts 250/185a carb specs

[TT5 Matt]

hi all
has any one got float levels/carb specs on the twin cable ts250/185a carbs?
a old mate gave me a tray full of 185 and 250 carbs and other useable spares and i like to try a 250 carb on my rm185 project to get a bit more poke from the doscile little motor, the a model 185 doesnt seem to have much of a chance to fit a bigger carb than 28mm because of the spigot intake on the barrel is there any way this can be changed to open up the intake port like the rms125?

TT5 Matt

[pokey]

seems you need to ask your mates who has access to a millimg machine.

 Performance what it seems your after aint just about bolting stuff on. its more about making what ya got work better.
  Id be gettin a bit of advice on  ports  before playing with carbs , after all they are the bit that sends the charge to be burnt.. crap ... then the pipe comes into play

 Just dont seem to end

[TT5 Matt]

hi Pokey
yeah im used to 4 pokers and a carb and baffled oversize hot dog got things going nice and abit more comp worked well,i figure that if i get more in the c/case you need more transfer port area to take advantage of the increase same goes with the exhaust port,i intend to lift the t/fers and exhaust ports 1 mm and open out the intake.i have access to a mill,lathe and tig so whats the go on the intake mod?i also have a rm125m pipe been cut/shut for the 185 but would like a rms pipe [made out of unobtainium]maybe c/god can find one!!
shame ts250 motor wont fit that size frame.

TT5 Matt

[cyclegod]

Heres a pipe specifically for the 185, the jerk listing it insists its a TM125 pipe, even though I have the exact same pipe for my TM/S 185, and I sent him photos proving that it's from the 185 hop-up kit. He lists occasionally an airbox for the TM125 but its just the kit airbox as well and doesn't fit the TM frame, I told him that as well as photo proof but he's listed a bunch of things like this what a wanker.

I hope you have deep pockets as the current winning bidder is "mikebfym" a notorious cashed up yank who seems to have unlimited resources.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=008&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=180233713828&rd=1

[pokey]

This is a 74, unsure if its the same as an A model bore but anyways...











Dont remove the bridge on the intake, it needs that.
 From the pics its pretty easy to see the restrictions but widen the ports so she can breathe as its better than playing with heights as that changes engine characterists.
The issue with the intake is those studs  restrict what size carb  can be bolted on or  working out how to move them to suit what carb you have .
 Cant find my details but the optimum size carb for that cubic capacity should be about a 36-38.

Thats all well and good but will do stuff all without a good pipe matched to that engine. a 125  pipe suits a 125 not a 185.  A 2T engine uses a pressure wave  in the chamber to scavenge the ports to remove burnt and unburnt gases and then reflects some unburnt gases back into the combustion chamber  sort of like supercharging. Thats why a good pipe built for that engine is crucial in making the engine work.

 Are a few other things you can do depending on what your going to use the engine for.

[Lozza]

Raising the EX and TX port height will just shift the power up the RPM range.There is a bit more to it than the port windows.The duct angle and shapes are a big influence to. Then there is ignition, cylinder head etc etc.However it all must match the gearbox if it doesn't match the ratios well it will be slower than an 80.
With these barrels the transfers(or lack there of) is the biggest hurdle to overcome. Good news is that there is several ways around the problem.

[cyclegod]

Good news is that there is several ways around the problem.

Which are?.......

[Lozza]

Major surgery, not for the feint hearted.Students of Hans Hummel(or copying a Ma*%o barrel)  will know straight away what to do. All will be revealed when I get a TM 125 done.I've probably mentioned what to do on Graeme's TM 125 thread already;)

[TT5 Matt]

i give up,with a spigot hose joint carb to restrict on carb size although the barrel has 6 tx ports sooo ill put it together with the bits ive got and just flog the fork out of it till it dies and than build another tt500 for some real power using brentj handling mods to get the dinasor to handle

TT5 Matt

[LWC82PE]

do you have a rubber manifold set up that mounts with 2 screws to the cylinder and the carby is a push fit in the manifold? if its this type you can use aftermarket Mikuini manifolds that allow the use of a bigger caby. also with some smart thinking its possible to make an adapter plate to space the holes out wider. you do this by making a wider plate with holes out wider and then drill counter sunk holes to and use counter sunk screws to holt the adapterplate to the cylinder. so the plate has 4 holes. 2 normal holes for the manifold, and 2 counter sunk holes for mounting adapter plate to cylinder. you can also weld this plate to the cylinder and then not need teh countersunk holes and screws.

the real issue with bigger carbys in 185's though is the height. you can only go so big as the float bowl on many carbys hits the cases. thats what was the limiting factor on my 185. plus i wanted to use a air box so the length of the carby also came into it. you maybe could angle the carby upards but i think that would upset the floats/float level.

[TT5 Matt]

hi all
got out some hose,carbs and verniers and 32mm carb is a doable project with good clearence on the cases while leaving enough meat on the pipe type inlet manifold and the inlet port is bridged to allow for a good open out session with the rotary files a bit like dt175 verus it175 barrels

TT5 Matt