hi i want to get a 70cc kit put on my bike. either malossi or polini. can anyone tell me all the things i need to make it run properly with this kit fitted. thanks
seen as you haven't bothered to look il assume someone else is fitting it? if they are let them deal with it and just pay them through the nose for it!
If you want 'the lot' be prepared to spend some serious moolah, as you'll need an uprated crank, a sports variator, a decent sports exhaust pipe such as a Yasuni R or a Leo Vince ZX, uprated clutch springs and contra spring, and a bigger carburettor that's re-jetted to match the new exhaust and that's not a complete list. You may decide that shopping list is worth more then your bike, depending on how old your bike is. Putting a larger bore kits and lots of sports extras without uprating the crank is asking for trouble, as the 10mm small end won't take the revs that the Malossi or Polini port timing can provide without either snapping the con rod or smashing up the small end bearings, resulting in a ruined engine. If you want to spend money on your bike, go big or go home.
We ran a polini 70 cast barrel on a zip with std crank without any issues for over 8000 miles. We ran a 21mil carb jetted to suit mated to a racing inlet and polini pod filter. It had a malossi varator and uprated clutch spring. Original exhaust was a Leo TT which ran great and put out a fair amount of power. i clocked the ped at 70 with the satnav We later changed the pipe for a Polini 9 (cant remember exact lettering but it was £300+). the pick up was improved but we sold the ped before fully sorting out the jetting
The problem is we don't know how old or worn his existing crank is, so I was erring on the safe side.
The bike is a 2010 zip sp liquid cooled with a stage 6 clutch,variator and rollers and a pm 360 exhaust.
but what sort of milage has it done and when was the bottom end last rebuilt???? Ours had done 6K when the 70 kit and associated mods were installed
If theres no obvious play then i personally would risk the std crank. The risk of failure is minor. Its more likely to wear the bearings first which you'll hear. You can then swap for a performance item. If you went that way to start with would have to strip the casings anyway...may as well get some use from the std setup and delay the strip IMHO....you takes your choice
At the moment it runs like shit when I start it and pull the throttle it just sits there revving for about 5 seconds then moves off slowly losing power slightly then pick ups a bit. And also I was hitting 55mph about a week ago now I can barely get. 45 out of it could the rollers play a part in this?.
piston rings could be on the way out , does it start easy ? if its lost power all of a sudden after doing a top speed run id compression test the top end
even with lowish compression it'll still start.and its more about the colour of the plug not how clean it is. A dark sooty plug will tell you its running rich, a light colour its lean. Needs to be a med grey/brown. Have a look at images on the web or theres a section in any haynes manual that shows you how it should look
if it's an electric choke model, the choke may be stuck on. Take it out, clean the choke and chamber and try it again after cleaning the plug. Also check the air filter and make sure it's clean.
http://www.scootershack.co.uk/threads/carbs-what-is-what.32724/ this should help - First Vid, 4 minutes 1O seconds - but hey - watch the lot. Can't hurt.
