replacement large block kit

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paul213
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looking to retire my home tune v1 mugello 225 it has a little to much exh & inlet timing ,
so what i'm after is a kit that will pull 7500rpm on 4.8 sx box with a devtour and 30mm (this is flat out on the level in good conditions not every day) must be left hand carb as after owning scooter for 28 yrs I still cant bring myself to cut off the battery tray.
does anyone know the port timings on a mbgm rt225 I built a original rt one for someone but seem to remember reading the the timings were revised for the bgm version.
speedy
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I would think if your criteria involves left hand carb exit, then for reedvalve the gt200 fits that description or old school piston port, then the Avanti. Two mates now have Avanti's and rate them highly. Not sure what the Avanti revs to, but one has sx gearing and pulls very strongly through the box. The gt is what I'm gonna be buying in November for a winter build and I shall be using the same ratio gearing, however not with a Devtour.Hope that helps in some waycheersSpeedy.
Last edited by speedy on Thu Sep 25, 2014 8:23 pm, edited 1 time in total.
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Speed Demon
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RT should fit the bill. The other option is GT 200. See Eden's thread about those.
Get to SULK
shocky
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Did I really sell that scoot over 28 yrs ago to terry parker for 225 quid
We sleep soundly in our beds because rough men stand ready in the night to visit violence on those who would do us harm
slangen
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My GT186 with phbl25 and taffy Mk4 pulls sx gearbox and S2 easily. I can sit at 7000rpm all day long true gps at 120km/h. No problems keeping up with 240 mugellos and standard ts1:s. Never tried the top speed but was sitting at 127km/h for a while, should be around 7500rpm. Guess the mk4 will close down at 7800 or somewhere around there. I have just matched the case and cleaned up the ports.

I am awaiting a GT 200 from the UK now that will have a VHSH30 and L+S Stealth Tourist.

My GT186 is amazing so I have very high hopes for the GT200.
Jazzy
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Avanti for me, beats my mates rt225 in all Departments.
But that said he loves his.
Can you have a 30mm on the left with a gt.
slangen
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I was told it is possible to have a phbh30 and possibly a vhsh30 that is a flat slide and a bit taller. Eden might fill in I think he runs a phbh30 on the left.
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corrado
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GT200 has 4 inlet manifold configurations, 2 on each side.

Left hand 25 mm size for PHBL25 and Mikuni TM24 [probably others too, the outer diameter is 30mm] and left hand side 30mm [35mm outside diameter] for PHBH30, VHSH30, Mikuni TMX27 & 30, BGM & other Keihin copies.

The 2 right hand side inlets are for 30mm or 34mm carbs, I'd imagine [as I've not seen them in the flesh] the outer diameters are 35 & 44mm respectively.
eden
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yes you can run 30mm on the left, im running 30mm on the right because I have packed up my reed block.
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coaster
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paul213 wrote:looking to retire my home tune v1 mugello 225 it has a little to much exh & inlet timing ,
so what i'm after is a kit that will pull 7500rpm on 4.8 sx box with a devtour and 30mm (this is flat out on the level in good conditions not every day) must be left hand carb as after owning scooter for 28 yrs I still cant bring myself to cut off the battery tray.
does anyone know the port timings on a mbgm rt225 I built a original rt one for someone but seem to remember reading the the timings were revised for the bgm version.
Or you could stick a read valve on your muggy which would tame those port timmings?
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