Beaver Posted November 22, 2020 Share Posted November 22, 2020 1 hour ago, tortron said: Gona put a gn250 rear sprocket on (43 down to 41) Top gears going to be useless now, not enough power At least you're realistic **Insert smiley face** Quote Link to comment Share on other sites More sharing options...
tortron Posted November 22, 2020 Author Share Posted November 22, 2020 More cubes more torque I want to drop the rpm at 100 from redline down to the on cam area rather than trying to BREAK THE LAW GOING 105 1 Quote Link to comment Share on other sites More sharing options...
Beaver Posted November 22, 2020 Share Posted November 22, 2020 Thank you for your service. Quote Link to comment Share on other sites More sharing options...
keltik Posted November 22, 2020 Share Posted November 22, 2020 1 hour ago, 00quattro00 said: When are you putting it on a dyno to see how much power it's making now Turn up to J5s earlier on Thursday and I'll convince the local bike shop guy to let you do some pulls Quote Link to comment Share on other sites More sharing options...
tortron Posted November 22, 2020 Author Share Posted November 22, 2020 That's very chur because I will be there Thursday arvo Quote Link to comment Share on other sites More sharing options...
tortron Posted November 22, 2020 Author Share Posted November 22, 2020 Was going to chop up a gn250 chain guard , drill it full of holes for oldschool racer look Turns out it doesn't fit. I wonder if gn250s have a longer swing arm. Gn250 one weighs 700g Gn125 one weighs 430g Very solid 1 Quote Link to comment Share on other sites More sharing options...
hampie Posted November 23, 2020 Share Posted November 23, 2020 1 hour ago, tortron said: Was going to chop up a gn250 chain guard , drill it full of holes for oldschool racer look Turns out it doesn't fit. I wonder if gn250s have a longer swing arm. Gn250 one weighs 700g Gn125 one weighs 430g Very solid I bought a box of gn 250 parts from a guy who has a 125 and he thought he could swap things over too, apparently they are quite different in the rear. Seats aren't easily interchangeable between the two either btw Quote Link to comment Share on other sites More sharing options...
tortron Posted November 27, 2020 Author Share Posted November 27, 2020 Looks like 2 hours of riding was enough to warm the engine up enough to kiss the valves - very slight witness marks in the carbon of the valve cut outs pretty dumb wanna know what i think the issue was its very dumb i just lined up a couple of the 150cc kit pistons. They are all different fucking heights. The last one i took out had good clearance but the one i put back in was half a mm taller on the edge , Theres one sure fire way to get this engine to work, and thats to bore it out to 165cc because the piston is a much better match tot he head 5 Quote Link to comment Share on other sites More sharing options...
tortron Posted November 27, 2020 Author Share Posted November 27, 2020 also if i take the bore out as far as it will go and stroke the crank as far as i have seen done you can turn this 125 into a whopping 230cc beast For way more money and effort than simply putting in a dr200 engine, which can easily be bored out to 230cc and for way less reliability so i will probably do that in the future 3 Quote Link to comment Share on other sites More sharing options...
M.H. Posted November 27, 2020 Share Posted November 27, 2020 Are you going to melt down some more of your titanium cutlery to make some light weight valves? Quote Link to comment Share on other sites More sharing options...
tortron Posted November 27, 2020 Author Share Posted November 27, 2020 3 minutes ago, 00quattro00 said: Are you going to melt down some more of your titanium cutlery to make some light weight valves? not for this head, i already looked into it and would have to get valve blanks cut to length The gn head has tiny valves 25.5 and 22.5mm. DR200 has good sized valves but the ports and combustion chamber are too big unless you are running a big piston, which i might get away with with the 65.5mm one. Probably be perfect with a stroked crank too. Theres some quad bike heads that are better for what i want to do, im just waiting for the right one to come up for sale and then i will get titanium valves 2 Quote Link to comment Share on other sites More sharing options...
tortron Posted November 28, 2020 Author Share Posted November 28, 2020 Looks like I'm gone buy a cylinder that's already been sleeved and bored to 65.5mm rather than sleeve one of mine. Anyone want to buy a 150cc kit for GN or Dr (I have both pistons) I actually have 2 of them. Check the clearance and it should be fine with a normal boring cam lol Quote Link to comment Share on other sites More sharing options...
M.H. Posted November 28, 2020 Share Posted November 28, 2020 9 hours ago, tortron said: Theres some quad bike heads that are better for what i want to do Is this one any good? https://www.trademe.co.nz/2880016702 Quote Link to comment Share on other sites More sharing options...
tortron Posted November 28, 2020 Author Share Posted November 28, 2020 i think tat will be the same as a dr125 i want an lt185 head. but i might end up putting bigger valves in a dr125 head. I forget what lt160 heads were like, maybe one of those Quote Link to comment Share on other sites More sharing options...
tortron Posted November 29, 2020 Author Share Posted November 29, 2020 18 hours ago, 00quattro00 said: Is this one any good? https://www.trademe.co.nz/2880016702 oh actually it will be the same as a dr125 but, it and the dr125 have 30 - 26mm valves so would still be an upgrade. Quote Link to comment Share on other sites More sharing options...
tortron Posted November 29, 2020 Author Share Posted November 29, 2020 Model...... valve size mm... in ...... ex.....length mm..in..... ex DRZ/LT125..................... 30....... 26.....................90.3...89.3 LT160............................ 28....... 25.....................91.9...91.0 LT185............................ 30....... 26.....................90.3...89.3 DR200............................ 33....... 28.....................89.97...88.77 LT230............................ 32....... 28.....................88.66...87.84 LT250............................ 33....... 28.....................88.57...87.84 LT300............................ 33....... 28.....................88.57...87.84 Quote Link to comment Share on other sites More sharing options...
tortron Posted December 31, 2020 Author Share Posted December 31, 2020 Hotcam, (what came out of a)DR125, gn125 Looks like the Dr one has a tonne of duration on it so it might be an old dr200 cam. Should measure it. Cam "bearings" I. The dr125 head got a bit chewed as they all do in these engines, but I should be able to lap a little off the mating surfaces and run a reamer down to remove the worst of it 1 Quote Link to comment Share on other sites More sharing options...
tortron Posted December 31, 2020 Author Share Posted December 31, 2020 Quote Link to comment Share on other sites More sharing options...
tortron Posted December 31, 2020 Author Share Posted December 31, 2020 Oh also the DR had dropped a valve as well. The tip of the valve was gone (and the spring etc for that valve was missing so someone opened it up I guess) and both valves bent. I just happen to have new valves already 4 Quote Link to comment Share on other sites More sharing options...
tortron Posted January 25, 2021 Author Share Posted January 25, 2021 Got some genuine China parts 6 Quote Link to comment Share on other sites More sharing options...
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