kenDAWG Posted October 21, 2012 Author Posted October 21, 2012 well if its blue-print it will have its ports tweaked and everything am i correct? still think £400 is a lot though considering its a re-bore of your own cylinder, and not a pistion/gaskets/cylinder/head and barings. and even if it was i still think £400 was a bit much. cant really see how a re bore tweak + piston would be much more than £250 personally. But i could just be being cheap again. id probably "if i needed a rebore" just go up the 0.50 or or whatever the next available size is and get the piston/rings for that. i dont think that would be any where near as expensive as 400. as far as im aware it is a cylinder and head rebore along with all gaskets and small end barings... im not sure what blue print means-ill have to look into that. its the same price as a athena 170 topend then obviously tou get a whole new topened "no rebore" i know its expensive but im worried the 170 will destroy me bottom end, crank and barings etc ken
Moderator Airhead Posted October 21, 2012 Moderator Posted October 21, 2012 as far as im aware it is a cylinder and head rebore along with all gaskets and small end barings... im not sure what blue print means-ill have to look into that. its the same price as a athena 170 topend then obviously tou get a whole new topened "no rebore" i know its expensive but im worried the 170 will destroy me bottom end, crank and barings etc ken Blue printing is checking the transfer ports match up exactly to the engine cases with no steps, and that all the ports are covered/uncovered by the piston at exactly the same time. Theres no such thing as boring a cylinder head...Just skimming them for the optimum squish clearance so I'd guess thats what will be done there...This does increase compression ratio though which may not be a good thing on this bike?
kenDAWG Posted October 21, 2012 Author Posted October 21, 2012 sorry yes i know that the head gets skimmed and barrel gets bored out just a little drunk after watching the newcastle v sunderland match so the bottom end might not be able to handle the compression on the rebore and skim? what about the 170cc kit im sure the compression would be more with this kit? i seriously done know just looking into my options! ken
Moderator Airhead Posted October 21, 2012 Moderator Posted October 21, 2012 The 170 kit comes with a cylinder head...It's a fairly common upgrade so you should expect they have got it right? Are you not concered about the insurance implications of this?
kenDAWG Posted October 21, 2012 Author Posted October 21, 2012 i will worry about the insurance once i make a decission, im more worried about my mortgage to be honest lol... i just thought the 150cc would be less strain on the bottom end than the 170cc but i suppose there is more factors involved than just cc gain. ken
shambles1980 Posted October 21, 2012 Posted October 21, 2012 even just making the ports optimal would make a diference at stock cc, usually blue printing is something you would do to a race day bike. under the assumption that its going to last the season. but probably going to need a rebuild at the end of it. dont know what you would expect of it if your going 25cc bigger and getting it blue-printed its going to be a huge diference..
Moderator Cynic Posted October 21, 2012 Moderator Posted October 21, 2012 No blue printing will make a big difference if the entire motor is done. Making sure every single part is as per the engine builders design re balance etc. Bluw printing a 2 stoke barrel dont make me laugh. Call stan stephens and see what he says to it. After he stopps laughing. I have some elbow grease i could let you have cheap.
kenDAWG Posted October 22, 2012 Author Posted October 22, 2012 cynic you can hoy that elbow greese up your clacker valve i got my own!!! anyway on a serious note the feelings are that its a waste of money and the fact my little bikes bottom end might not be able to handle the compression... hmmmm...
dt502001 Posted October 22, 2012 Posted October 22, 2012 If done properly the comperssion ratio will stay the same with either the 150 or 170 kit.Thats why they want the head to reshape the squish area of the head.They most likely will chuck it in a lathe and remove whats nessary to keep the compression the same due to the flat top pistion, The compression ratio is caculated by the area left when the piston is at TDC.It's been quite a while since I have done it I would have to look up the exact formula but it something like swept volume-total volume.My budy has a ktm125 with a factory 135 kit and what a different bike it's is. It's not the compression that would kill the bottom end it's the added weight,if the pistion is forged vs the stock cast it might weigh the same that would be my? to ask the guy doing the work.
kenDAWG Posted October 22, 2012 Author Posted October 22, 2012 If done properly the comperssion ratio will stay the same with either the 150 or 170 kit.Thats why they want the head to reshape the squish area of the head.They most likely will chuck it in a lathe and remove whats nessary to keep the compression the same due to the flat top pistion, The compression ratio is caculated by the area left when the piston is at TDC.It's been quite a while since I have done it I would have to look up the exact formula but it something like swept volume-total volume.My budy has a ktm125 with a factory 135 kit and what a different bike it's is. It's not the compression that would kill the bottom end it's the added weight,if the pistion is forged vs the stock cast it might weigh the same that would be my? to ask the guy doing the work. very helpfull post indeed... you see i dont want much cc i just want a little bit more hp so i can go up a tooth on the front sprocket - im not into the bike screeming at 60mph so i would like a little bit snappy for greenlaining and a little more topend for road use! so in your opinion the rebore is something worth investigating further? find out what the piston is made of? cheers ken
dt502001 Posted October 22, 2012 Posted October 22, 2012 From your post above it says the piston is forged,so the only ? is how much more wieght is or is not being added.As in the same post it states that the barrel will be replated,, so you have no bore over options.Just replace the ring yearly and if it get dammaged you have to replate the barrel. I am not sure if you stock barrel is nickelsil if it is than you have no over bore avilable now,, if it's dammaged then your looking at a new barrel or haveing it replated and that not cheap either way.
kenDAWG Posted October 22, 2012 Author Posted October 22, 2012 From your post above it says the piston is forged,so the only ? is how much more wieght is or is not being added.As in the same post it states that the barrel will be replated,, so you have no bore over options.Just replace the ring yearly and if it get dammaged you have to replate the barrel. I am not sure if you stock barrel is nickelsil if it is than you have no over bore avilable now,, if it's dammaged then your looking at a new barrel or haveing it replated and that not cheap either way. ok man i got that, thanx for your help... ill fire a couple of questions to the seller see what he says!! cheers ken
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