I will install this Polini 177 setup...Your opinions please?

Hi All,

After thinking on buying a stronger engine I will stick with my Polini 177 and configure as follows

Let me know if you think this setup is :

1.Reliable.
2.Good acceleration and good top speed (looking for 70 - 75 mph.
3. Any improvement or recommendations.

here we go…

1…Match the Crankcase to Polini 177
2.Increase the inlet
3…Upgear to 21 teeth cosa clutch + 65 PX 200 primary
4…Keihin PWK28 carb
5…Mazzuccheli race crank
6. SIP stainless steel performance exhaust.

If I go for this would what main jet would I use, what would the timimg be set to (18 degrees ?) and would I still use 9 grade plug.

Thanks and Regards,

Brian.

P.s I think you have made the right decesision which will hopefully be bourne out when the motor is built and it is burning malossi 210s that wont pull uphill!

Diablo,

Does Harry at Grand Prix also do porting work etc? I am still deciding who to send my engine to.

If so can you provide details.

Regards,

Brian.

An option you have available for the pipe is to have it powder coated.This is now available in a chrome like finish(see Magic’s Voodoo in last month’s Scootering).I know Aerocoat in Norwich do it and I’m sure any decent powder coater could do it for you as well.

hello,

I peersonally feel that 21/68 is a little shorty. 21/65 you know I can reccomand it with THIS KIND OF ENGINES (no big malossi with reed). And 23/64 is really too long. If you haven’t buy yet the gear department you could have a look at the recent entry in SIP catalogue of the 22 teeth renforced cosa clutch. Unfortunately they don’t sell the sproket separately.

For the carb you know that I like the keihin and that I think now it is the best carb for this size.

I think your proposition is a good compromise, but either open the inlet or use a racing crank not both togheter or you would loose too much down.
Or as Diablo suggested let somebody cut your crank in a more sensible way.

I personally would open the inlet port and cut the cranck less then the Mazzucchelli race. I would use the standard one since 1 on every 10 Mazzucchelli tends to give you problem. Don’t ask me why. It is just percentage. Diablo or somebody else of experience could tell if they found out the same thing.
So original crank cut, bigger inlet and with all the other ingredients that you have listed you will have what you are looking for.

If you want better cooling you could get a PX200 elestart flywheel, it gives also the nice classic vespa sound wind when you accelerate, and as you said 18 for the ignition and 9 for the spark.
For the carb set up ask when you are ready.

Don’t use the race crank because it has too much inlet timing.This will allow the bike to rev on and therefore possibly higher top speed but you will lose torque low down. If your px crank is in good nick then send it away to be split and a more sensible inlet timing used. I can recommend Harry Barlow for this and he can be contacted via Grand Prix scooters. Everybody knows how I feel about 21/65 set up but aside from that 21/68 will be more than enough. See the gearing calculator on scooterhelp.com. This also saves you the hassle of replacing the primary drive.
Be careful with the sip pipes some of them are very peaky. I would use SIP/JL Right hand or JL RZ left hand. I would also recommend strengthening the clutch bell and stronger springs either from Taffspeed or Worb5.
These are my recommendations hope they are of some help. See if Curare will oblige with the jetting.

Curare,

I am Scottish living in Ireland, I,m gutted we did not make it after nearly beating the Italian’s at Hampden.

Need the Irish to win on Wednesday so I can support a team in the world cup.

Regards,

Brian.

Curare,

So you think just add crank instead so no inlet porting required…so the job looks like this now…

1…Match the Crankcase to Polini 177
2…Upgear to 21 teeth cosa clutch + 65 PX 200 primary
3…Keihin PWK28 carb
4…Mazzuccheli race crank
5. RZ Evo left hand pipe

Do you think this will be reliable enough setup? and will accelerate OK up to 70 + mph even against winds and hills?

Regards,

Brian.

Hi Brian. Do you intend to do lots of motorway miles? If so you need a bike that will overtake lorries easily up hills into the wind etc. If you gear the bike too high there will be times when you struggle.So here is what you do. Buy a cosa clutch with 22 teeth. This gives the same ratio that Curare suggests but with 68t primary. If this is too tall 21t cogs are sold seperately and you can change the gearing to my suggestion without spliting the engine.
Also as Curare says you must open the inlet a little.I have just done one for polini and opened 6mm towards the back of the engine and 3mm forwards. I also widened slightly.The size of the inlet controls the volume of fuel and the crank timing the duration. As he also says they are suspect. If you do send your crank to Harry ask him to do what he does for me and he will sort it. Basically the mazzucchelis are prone to twisting. This can be sorted by welding the pin. Much better to use a genuine vespa crank.
Make sure you are specific with SIP when ordering. The LH RZ is stainless and the RH isn’t.
Hope this all helps

hello,

I can’t say anything about the shop, but if Diablo can suggest you they should know what they are doing.

Everything has been said so now you have to decide.

About Switzerland quilifying: I am Italian and my team quilified already. But I like the Irish…

Original von pyperb: Curare,

I am Scottish living in Ireland, I,m gutted we did not make it after nearly beating the Italian’s at Hampden.

Need the Irish to win on Wednesday so I can support a team in the world cup.

Regards,

Brian.

Well that’s you buggered then.;D

Diablo,

Interesting you suggest 21/68 which could save some money, I had someone else suggest to me malossi 23/64 and I know Curare likes his 21/65…so many options. I will not be doing this work myself, I will be getting a pro to do this over winter so it’s ready for next summer.

I may go for the RZ left for the torque you suggest, that SIP polished sure is a nice pipe though…can the RZ be polished?

I like your suggestions to reach the desired speed of 70 mph + and also keep it torquey.

I appreciate the input

Brian.

Hi, if you take into consideration the reed intake this will be my tip:
http://forum.sip-scootershop.com/en/thread.php?id=1642&start

[:rotate:]

You could look for the Malossi Reed & Manifold, Worb5 crank, 1,5mm spacer, widen the exhaust port 2mm (maximum!) per side and there ye go!!

Cheers,
Matt

Yes Harry ports. I do not wish to spam but I also run a workshop if you want them doing email me and I’ll talk it through with you.

All,

Thankyou for your input, I love this board, cant beat it with a big stick…

Ok then, this could be the setup I implement unless any one else has opinion:

1…Match the Crankcase to Polini 177
2. Increase the inlet
3. Cut crank by Grand Prix Scooters
3…Upgear to 21 teeth cosa clutch + 65 PX 200 primary
4…Keihin PWK28 carb
5. JL RZ Evo 2000 Left hand
6. Strengthen the clutch bell and stronger springs either from Taffspeed or Worb5.
7. 18 Degrees for the ignition and 9 grade for the spark.

Couple more questions…

Will I be increasing the inlet by 2mm top and bottom?
With this kit will my scooter sound beefy…better than the simmo?
Do you think Switzerland will qualify for the world cup against the Irish ???

Thanks and Regards,

Brian.

Geoturbos suggestions are good but you will increase ring wear with the port widening. I would keep it simple. The JL RZ pipe is left hand and also stainless so polishes up just fine

Perhaps you can help me.  I have an LML engine in a VLB.  I installed a 24/24 carburetor, Mazzuccheli race crank, Polini 177 kit, and mostly recently, a LH SIP highperformance pipe.  I think it runs a bit lean.  I live at 4,300 ft (1,280 meters).  Any suggestions on changing my main jet to a different size?

Any advice would be very much appreciated.

Gary