dt502001 Posted February 12, 2014 Posted February 12, 2014 Yep good point RZR a little thing like matching the ports(blue printing) is often over looked and so simple to do,, same with the cylinder base gasket they all need to be trimed/matched for good flow. A proper trimed base gasket can yeild 1-2 hp alone with matching ports ,,knife edge the intake bridge and 2-3 more hp with the bottom matched.Them motors wernt hard to get a extra 5 hp out of just by blue printing the motor from the intake to exhaust. This should be a very nice finnished project with all the new NOS parts Just in case you don't know how or what blue printing is ,,it's simple just get blue tool makers ink and assemble everything where the ink dosent make a imprent then it needs to go/ be matched small amount of work = big gains
rzresurection Posted February 12, 2014 Posted February 12, 2014 Trim the base gasket to match the port openings. Then transfer the base gasket to the case. Trace the gasket on the top of the case. Some layout dye will help. Take a dremel with a carbide cutter and cut to the scribed pattern. It's not to hard to do. Very worthwhile.
Calum122 Posted February 13, 2014 Posted February 13, 2014 I dunno. Not sure I'd trust myself doing that. I can't do it now anyway engines back together.
rzresurection Posted February 13, 2014 Posted February 13, 2014 Next time. If you ever want to try it, I'll walk you thru it.
Calum122 Posted February 13, 2014 Posted February 13, 2014 I've literally just sent barrel to be ported. WIthout the crankcases being done it's pointless I take it? It's for my TZR 4DL project.
rzresurection Posted February 13, 2014 Posted February 13, 2014 No problem, they can be done separately. There are hp gains to be made in both places. Any 2 stroke can benefit from it. There is always a mis-match when parts are cast. When the case is not 'matched' to the cylinder, the flow becomes turbulent where the base gasket sit. There is not a smooth transition at this point because the base gasket protrudes into the transfer port. By making sure everything is matched, you get smoother flow. Smoother flow means a better charge. Better charge means more hp. If you can do the work yourself, it's free hp
rzresurection Posted February 13, 2014 Posted February 13, 2014 I've literally just sent barrel to be ported. WIthout the crankcases being done it's pointless I take it? It's for my TZR 4DL project. Nice bike BTW. I'd like to see some pics of it. Always love seeing those smokers. Especially Yamaha ones.
Calum122 Posted February 14, 2014 Posted February 14, 2014 Haha, Unfortunately It's not a 4DL bike. It's just the motor that i'm dropping into a Yamaha DT125RE that I supermoto'd using Aprilia RS125 Wheels and WR450F forks. I've got a tasty little mod being hand made as we speak. Should look to get it on in a couple of weeks. Very excited.
rzresurection Posted February 14, 2014 Posted February 14, 2014 That's a cool build. Kudos for the work that you've done so far.
Moderator drewpy Posted February 14, 2014 Moderator Posted February 14, 2014 did the port matching on the Gilera, 1 hp extra on that is like 15% of total HP
blackhat250 Posted February 14, 2014 Posted February 14, 2014 That is a massive gain drewps,,, .shall it be fit for foamys DT50 in a drag at squires..
Moderator drewpy Posted February 14, 2014 Moderator Posted February 14, 2014 That is a massive gain drewps,,, .shall it be fit for foamys DT50 in a drag at squires.. still got to get it registered then fit the spanny and then dial in the carb settings. not sure if I'll go on it, I'll see nearer the time
dt502001 Posted February 15, 2014 Posted February 15, 2014 He Jeff the bridge in the cylinder port ,,,knife edge it up about 3/16th of a inch and finnish up your porting with a 80 grit finninsh stone you will have to keep it oiled and work at a slower speed RPM wise so it dosent plug up with mettal but it more free hp. And its easier to see any low/high spots you may have created in the roughing stage basicaly your at a stage 2 port now stage 3 is all the stuff I said above
rzresurection Posted February 15, 2014 Posted February 15, 2014 Hey Flip, I was thinking about the knife edge, but there seems to be a big debate on the RZ forum over it. A lot of the more expert tuners are saying that the knife edge was the NOT the way to go. I had always thought it was better. They are saying that a rounded edge is better. I just left it rounded as I wasn't ready to commit to the knife edge - I can always knife edge it later. Harder to put material back on than it is to take off. I also need a 90 degree grinder. I need to get in the areas where the ports enter the cylinders. Just need to clean more of the casting flash better. Good tips though.
dt502001 Posted February 16, 2014 Posted February 16, 2014 ER Um we just jacked his thread ask me on your build I want to see how this turns out
rzresurection Posted February 16, 2014 Posted February 16, 2014 Sorry about the slight hijack Stevec. All applicable points that apply to 2T's
Calum122 Posted February 18, 2014 Posted February 18, 2014 Cheers Rez. I'm waiting till I can get my hands on a car so I can take it off the road properly.
stevecarpy Posted March 19, 2014 Author Posted March 19, 2014 Hi all, sorry it's been a while. The build has progressed slowly and had to stump up some cash :-( Gearbox components went in To be fair that was easy but I had bag and tagged everything. Next thing was to drop the crank in
stevecarpy Posted March 19, 2014 Author Posted March 19, 2014 I Yamabonded the crankcase half and put the 2 together and torqued up Time to start fitting the outer components Clutch basket on Electrickery on Then disaster struck Decided to bite the bullet and bought one of these - hmmmm billet porn :-) Hardest part was drilling off the old gear ring without wrecking everything but that was successful Fitted back on engine Sorry about the pic heavy post, I'll put the others on shortly Cheers Steve
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