t5 jetting

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smoore-gt225
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hi tried to look for jetting advice but couldn't find any
so here goes I need a close jetting for a t5 with a phbh 28mm delly on and a simoninni pipe
can anyone advise me please
cheers steve
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coaster
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I had a 28PHBH on my old T5 with a standard looking performance box pipe (forgot the name) from memory it had a 55 pilot, 40 slide, x2 needle and I THINK a AV 266 atomiser, the choke was a 70. The jetting is scribbled down in a note book at home but I'm at work at the moment, I'll double check tomorrow. It ran very nicely with that on, I replaced it with a Spaco copy of the standard 24mm but lost a lot of top end.
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coaster
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Ok, I I just checked the notebook and I was a bit out :oops:

The settings were:
Main - 115
Idle - 63
Choke - 70
Slide - 40
Needle - x6
Atomizer - AV 264

I ran it routed through the air box but without filter.

colin
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smoore-gt225
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hi coaster I bought this t5 engine and it came with a malossi manifold etc fitted but for the life of me I cannot get it to run properly so I took it apart and found that it has been ported etc and the sealing pad has been removed and the crank has been ground down, now I don't really know Vespa's but does this need to have a reedvalve and not just the big carb to work properly or can it run just with the big carb
also it keeps blowing at the head do t5's have a head gasket as bought a set and didn't have a head gasket in the set
cheers steve
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coaster
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I'm not certain but I THINK mine had an ally head gasket, I could be wrong though :?

Not able to help on the other issues as despite running the T5 for a couple of years I did nothing more than running repairs really, I'd repost as a separate question, plenty of Vep experts on here 8-)
soulboy
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that needs a read valve and your head sounds slightly warpped mate
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joeythescooterboy
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It looks as though someone has had a half arsed attempt at porting for a reed but sealing pad is still there so it's going to be difficult to get it to run properly without a fair bit more work.
Nemo saltat sorbius, nisi infanus est.
Jack221
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Steve, Yea, this has been butchered. Reminds me of some of my tuning 30 years ago :D

Assuming you have shown us the worst of it. If you just get rid of that ruined crank then it might be ok. It will just about be ok without a reedvalve. At high rpm the inlet valve sealing pad actaully sealing is less important. Get a race T5 52mm crank or a longstroke 54mm T5 crank and if the rest of the engine is all ok then you will have dodged a bullet.
Vespa est ieiunas, quia semper operaturi
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