Mugello 225

[SILGP]

Hi, the top speed on my mugello 225 is 64mph. I have a 30mm dellorto (setup at Chiselspeed) and a CST3 exhaust. 18/47 sprockets and Indian GP200 gearing.
My question is, is that slow or about right for a muggy ? I was expecting more tbh.

[Fish]

I had the same set up, sorted by Chiselspeed as well (although I did have a MTECH unit fitted, and a LI125 gearbox, 18 x 47, which I think has same final drive as GP200)

Took it to Elvington Sprint Day and went though 1/4 mile at just over 71mph

(16 stone pilot - don't know if that factors in the equation)

I have the dyno charts somewhere

[SILGP]

Cheers for the reply. I'm about 11 1/2 stone so possibly should get a bit more out of it

[ULC Soulagent]

Should be hitting at least 70 mph

[Knowledge]

The issue with the 225Mugello is that it is a bored-out version of the 200 and the transfers have been set-up for the 200. Due to the angle that they enter the bore on the 200, when the barrel is bored out for 225, it effectively reduces the height (duration) of the transfers. The result is a bigger capacity with a reduced transfer timing.

When I built one at the beginning of the year, I was offered a 58/115 crank. I used a 9mm packing plate which put the A transfers at 122.6 degrees, which was a big improvement over the 116.7 degrees obtained with the 8mm packing plate.

The inlet reduced from 161 to 159 degrees (good) and the exhaust was up from 178 to 182.7.

I don’t recalling doing any porting work as such, and concentrated on getting the squish and CR into the right ballpark.

He saw 76.8mph on his GPS recently.

[dscscotty]

if your running a CST3 Touring pipe and GP200 47x18 @ 5.22 it'll be well under geared, CST's are great touring pipes, which require taller gearing, it'll be running out of steam @6500rpm,
Try gearing to around 4.7-with 47x20 or if the port timings around decent 4.6 -46x20,

Good Luck

[SILGP]

Thanks for all the replies. I think l'll try changing the front sprocket first and take it from there.
Cheers.

[Rich Oswald]

In my experience the port timings on Muggy 225's are usually way out. I have a Version 1 which was stifled but a Chiselspeed touring tune sorted it and it was a good long lasting kit which would do low to mid 70's. I have a V4 on my Gp with Taffy Mk4 and 30 phbh, 5 speed Cyclone and it will do 75mph gps on a good day.

I really think you should be getting more from yours as I am around your weight. Have a look at the gearing as Scotty says.

Rich'

[citydaz]

I got 63mph from my Mugello 186 when i had it dynoed a while back.
However ive lost 15kgs since then so it should go faster now!

[Knowledge]

Well done Daz.15kg loss is well impressive.