Boost Port for reed valve conversion

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ulyssescale
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I installed an LTH reed manifold on my iron 200 barrel. Without the boost port cut into the cylinder the engine would lose power quickly at higher rpms. With the boost port, the engine revs out much much higher.

If you simply want the benefits of reed valve but won't be going onto the highway (motor carriage way - whatever you guys are calling it now), I can see skipping the boost port. But the benefits of the additional work to do it is considerable.
A chicken ain't nothing but a bird.
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corrado
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I've had mine over 70 on the motorway with some to spare and that's with a low revving exhaust. That's without a boost port.
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mawso
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That's good to know Martin, as mine's also a V1 225 Mugello with Atomic reed + inlet boost port cut in too. I'm aiming for 4.7 with a Saigon Taffy. Do you notice a lot of difference between TM24 and TMX27 on top end?
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corrado
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I never got the jetting right with the 24, in fact I'm pretty sure I holed the piston with the 24 while doing plug checks that's how I came to fit the reed as I had a spare TS piston but no Mugello piston. I may go back to the 24 when I get something on the road to put my Imola engine back into as the 27 was off the Imola. When I built the reed set up I used a PHBH26 but couldn't get that running sweet hence sticking the TM27 on it.
YAMLAM
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"I never got the jetting right with the 24"

Im hoping to use The Tm24 on my reed valve 225 Rapido when it`s finished, as ive got one laying about. The guy doing the boost port on the barrel , said he jetted one in recently and it was an absolute bugger getting it right on the needle, so hopefully he will be able to point me in the right direction, followed up with plug chops on my part.
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corrado
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I persevered with the factory needle [5N13 from memory] others used a leaner needle [DH7 ? I think]. You can change the atomisers, think stock is P0, they go up and down in twos, N8 being leaner and P2 richer but I was told they make very little difference unless you jump by 3 or 4, ie N4 or P6 and as they're about a tenner a pop it soon gets expensive. Check the carb set up page as I think there's a couple on there that had good results with un-reeded 185 mugellos. Don't rely on my numbers as I'm going from memory.
storkfoot
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4DH7 I think. Generally leaner than the 5N13. Worked very well on my piston ported SR193. I'd happily use a TM 24 again.
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