SIL cast iron reed conversion

FREE tuning and maintenance info, plus links to our original tuning pages that started it all off.
Grant McLachlan
registered user
Posts: 28
Joined: Wed Dec 02, 2015 10:46 pm
Main scooter: Indian GP RT 225
Contact:

Hi has anybody converted a SIL stage 4 cast iron barrel to reed valve using one of the popular small reed blocks ? I'm thinking of doing this, adding a boost port and cutting a window in the piston. If anybody has done this was the results worth the effort and cost.
User avatar
corrado
Dealer
Posts: 2588
Joined: Thu Jan 08, 2009 1:12 am
Main scooter: Lambretta GP
Location: Top of Blackpool Tower
Contact:

I've done a reed conversion, small Atomic, on a 225 Mugello. I did nothing to the barrel I just fitted a TS1 piston and bolted on the reed which I flowed to the inlet port. Performs great.
I've got a few SIL 200 barrels which I thought would work well with an RB20 piston and TV rod as a cheapish reed conversion. When I spoke to AF about it they said I could just use a normal piston and crank but cut a half moon shape into the piston skirt. They said they only bother putting holes in the piston when the customer specifically wants them. Following on from that I cut a half moon shape in my TS1 piston. It was already running great so not sure if it added anything to it. Picks up far better from low down and now pulls taller gearing. I'm tempted to add a boost port but think it may be outside of my mechanical comfort zone.
Grant McLachlan
registered user
Posts: 28
Joined: Wed Dec 02, 2015 10:46 pm
Main scooter: Indian GP RT 225
Contact:

Thanks for your reply Corrado, I am going to make this a winter project, I have a cast barrel and piston on which to experiment and if I make a pigs ear of it, they are not to expensive to replace. Matching and flowing the reed block will be easy enough with the right burrs but I will have to read up on position of windows ( if I decide to put them in) and half moon. From memory I think there is some info on this site regarding the position of the windows. I just like to tinker and other than the reed assembly (that I could sell on evil bay if it doesn't work out) the investment isn't to expensive. Once again thanks for taking the time to offer your experience.
Andy W
registered user
Posts: 144
Joined: Mon Jun 25, 2012 1:39 pm
Main scooter: GP 186 Imola
Location: Emsworth, Hampshire
Contact:

I have converted a 200 barrel to 225 with a small Atomic reed assembly, fitted a TS1 piston, 28mm PHBH and Taffy copy exhaust. it took me to Italy and back for the Euro. Admittedly it only had just over 200 miles running in on it when we left and it did seize solid after 100 miles in France (55mph on dual carriageway), but after 1 1/2 hours it freed up and I drove it all the way there and back. richened it up after buying new needle and MJ.
once I returned I stripped it down cleaned up the piston, fitted new rings and it runs great now. well and truly run in now (1939miles). If this had been my TS1 it would have been end of rally and coming home on a recovery truck.
plus side I get about 15 miles to the liter as well. Glad I did it.
It's already for Spain next year, Andy
Grant McLachlan
registered user
Posts: 28
Joined: Wed Dec 02, 2015 10:46 pm
Main scooter: Indian GP RT 225
Contact:

Cheers Andy.
Post Reply Previous topicNext topic
  • Information
  • Who is online

    Users browsing this forum: No registered users and 16 guests

cron