Gilera Ice stage6 50cc cylinder kit. Questions

Hello I'm building a bike, Gilera Ice, to compete in the moped mayhem, as the rules state the bike cant' be over 50cc. When looking on the net for cylinder kit it seemed that the choice of 50cc kits wasn't as vast as the 70cc versions. Basically I narrowed it down to either a standard kit, an Athena kit. A polini kit or one by stage6. The engine isn't going to be used on the road only needing to last 2 1.5 hour races so a single ring kit seems to be the way to go. In the end I have got this stage 6 kit.


After having a quick look at it, compared to the standard cylinder it seems really quite similar in port lay out except the exhaust port which is massive on the stage6 cylinder compared to standard, with a bridged port. The cylinder is made form aluminium rather than iron so the whole kit weighs much less.


The head has a totally different shaped combustion chamber compared to standard.


Included in the kit are various thickness base gaskets, to aid with setting the squish, a head gasket, small end, gudgeon pin,gudgeon pin circlips, and a set of carbon fibre reeds. Basically every thing needed to fit it. I'm impressed for the money

What I was wanting to know is has anyone had any experiance of using this kit and what they thought of the parts? Also what would be the approx revs it runs best at and what sort of power i can expect from this cylinder with the right parts? I do plan on keeping the 17.5 dellorto that it came with unless it going to hold things back too much.

Thanks James

 

nice james keep us up to date, im not sure on your question however i am looking forward to the building process

 

Thanks for the feed back. Sounds like it should be very impressive with 8-10bhp probably a little way into the future yet but something to aim for.
As for the exhaust I think for now I will keep my eyes on ebay for second hand ones and try a few to see what works the best. I do have access to a sheet metal roller and a welder, just need to read lots of books on pipe design and have a few attempts at making a suitable one, but that will be a project for the distant future. Need to do alot of home work on that one first.

Cheers, I was pretty sure the carb would be good to use, dellortos seem to be rated highly.

Any ideas what sort of rpms the cylinder would be best work at?

 

Brilliant thats what I was hoping for a nice revvy motor, its going to run premix and no starter so there should be little extra drag on the crank to help with revs.

Looks like the cylinder would benefit from bit of a clean up of the ports and there is a noticeable step between the crank cases and the transfers. I presuming it would be benificial to grind and match the cases to the barrel in this area to aid flow?

 

Cheers Terro that is a great thread, thank you for the link. I have a good idea now of what should be done to the cases. Can't quite work out why the chemical metal was used though? I will give it a go as it looks like it would be beneficial and a bit pointless fitting the barrel with out doing it to get the best from it. Just didn't want to go grinding bits out without having an idea of where to grind. Picking up another engine tomorrow so nothing to lose. I did think about the main bearings thanks, just have to get some more and try not to be in such a rush next time.

 

Cheers Terro, the chemical metal makes sense now you've enlightened me. Any other tips you can give would be gratefully received before I go for it. The chemical metal has been applied to the cases and is curing, got my old die grinder out and cleaned the bits up so I'm pretty much ready to go once the chemical metal has had enough time to set fully. Once again thanks for your help.

 

Gave the grinding a go today and even though its a long way off finished im pretty pleased with the results so far. I've posted picture of it on my project bike build thread http://www.scootershack.co.uk/viewtopic.php?f=8&t=21548