Pinking with Scorpion and 210

Hello all.
New to forum (but not to thrashing the tits off vespas). I’m running a 210 with a T5 carb, 130 main, Be4, 185 air corrector, modified P2 pilot jet, fully retarded timing, de-restricted Scorpion pipe. Bike goes well (although a little more torque would be nice), it reaches a good turn of speed in 4th, but on occassions will begin to pink when flat out, and when I come off the throttle it starts to pink like buggery!

Not sure as to the exact specification of cylinder head as I bought the scoot with the kit already fitted and have been tweaking the engine since then, but the head appears to have been properly profiled for the 210 kit, it also has a short reach plug which was a bit of a surprise (never seen a p2 head with a short reach plug before, can anyone enlighten me on this?) and the usual 210 head gasket is present and correct. B9HS plug fitted.

I’ve read that stainless pipes tend to retain the heat more, would the pinking be because of this? If so would I be better off with an RZ left hand non-stainless or SIP Evo (don’t want a PM, had pinking problems with these before, but do want pipe with more torque than Scorpion), or is the problem more likely to be down to jetting?

Also, I have a 60mm crank in another engine which is unused at the moment so I’m thinking of swapping it into the 210 engine (running standard crank at the moment). Does anyone have any experience of using the Mazz 60mm crank with a Mallossi 210 and will this give me the torque I’m craving? Also what would be the best pipe for 210 kit and 60mm set-up?

Questions questions questions!! Hope some of the legends on here can help.

Cheers
Jonnystoned

This is common with 210s and to be expected with small carbs. The scorpian is quite revy so you will loose torque there. Stainless systems loose heat more quickly not retain heat. This is why the argument rages about whether they are alright on 2 strokes- sound waves travel quicker in hot air. 60mm crank will increase torque but setting one up is no easy task. I’m gona be getting my BRace pipe in the next coupla weeks so im reserving judgement on pipes till then. As Juan says it could be a flow problem but I just think std carbs are not up to the job of providing enough juice. Saying that there’s plenty who disagree. For me the 210 is best suited to reedvalve.
You could try increasing your slow running jet so it flows more when the throttle is shut.

hello and welcome,

I have just red your post but don’t have time right now for the answer. I will do it tomorrow or the day after.

This is the 'head you need.Or something similar.

The problem lies in the fact the Malossi is designed for a 57mm stroke therefore you’re messing with port timings.

I haven’t done this personally yet but Curare has some experiance of it I think.We discussed it a while back,I’ll see if I can find the thread.

Thanks for the links Juan K, excellent stuff. Given me plenty of food for thought…!

Cheers
Jonnystoned

This is common with 210s and to be expected with small carbs. The scorpian is quite revy so you will loose torque there. Stainless systems loose heat more quickly not retain heat. This is why the argument rages about whether they are alright on 2 strokes- sound waves travel quicker in hot air. 60mm crank will increase torque but setting one up is no easy task. I’m gona be getting my BRace pipe in the next coupla weeks so im reserving judgement on pipes till then. As Juan says it could be a flow problem but I just think std carbs are not up to the job of providing enough juice. Saying that there’s plenty who disagree. For me the 210 is best suited to reedvalve.
You could try increasing your slow running jet so it flows more when the throttle is shut.

Quick question here-are you running as fuel pump?

Cheers for the info guys. Not running fuel pump and the reedvalve is a good suggestion. Can anyone enlighten me on the short reach p2 head question? Haven’t seen one before.

Also, Diablo, you mention the 60mm option being difficult to set up correctly with Mallosi. What problems can I expect to experience?

I’m planning to install head packing gasket rather than base, have had experience of P2 with 60mm crank and uprated gearing (standard top-end) which went like stink when it was wound up on a long straight but would at times seem to mis-fire and have starting problems after a long run. Was this due to the packing gasket being at the base rather than the head?

Cheers
Jonnystoned

OK, thanks Curare.

Try this for size.

hello jonnystoned,

JuanK had the excellent idea of founding out a similar topic where this issue was discussed. (and seved me from a long writing. Tank you JuanK) If you don’t find there the answers you need ask again.