Dunkield Posted December 9, 2017 Report Share Posted December 9, 2017 On 7/12/2017 at 16:17, Albert 888 said: speed wise it's 40-45 flat and down hill with the wind behind me,headwind you can knock 5 mph off Does that motor not need a bit of running in? Just wondering if it is still a little tight that is all. Quote Link to comment Share on other sites More sharing options...
amateur Posted December 9, 2017 Report Share Posted December 9, 2017 2 hours ago, Dunkield said: Does that motor not need a bit of running in? Just wondering if it is still a little tight that is all. Running in? on a 2 stroke? Surely all you do is give it a blast, strip the top end, polish off the high spots on the piston with fine emery and you are good to go. Well ................ until you get that sudden lurch as it locks up solid Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted December 9, 2017 Author Report Share Posted December 9, 2017 4 hours ago, Dunkield said: Does that motor not need a bit of running in? Just wondering if it is still a little tight that is all. Not much to loosen up really only a couple of bearings and to run the bore in and bed the rings. Should be good to go from scratch. Im delving into the electronic wizardry of hpi cdi and curves at the moment. Chasing power and speed,Basically you throw your old points, stator,flywheel, coil away and fit an electronic ignition with a mini rotor,and a new cdi. This will retard and advance the ignition automatically once set up right. Quote Link to comment Share on other sites More sharing options...
amateur Posted December 9, 2017 Report Share Posted December 9, 2017 7 hours ago, Albert 888 said: Not much to loosen up really only a couple of bearings and to run the bore in and bed the rings. Should be good to go from scratch. Im delving into the electronic wizardry of hpi cdi and curves at the moment. Chasing power and speed,Basically you throw your old points, stator,flywheel, coil away and fit an electronic ignition with a mini rotor,and a new cdi. This will retard and advance the ignition automatically once set up right. Absolutely! With any bike, electronic is the way to go. Digital, even better, because you can map it to wring the last bit of power out Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted December 11, 2017 Author Report Share Posted December 11, 2017 Woop woop,from the Netherlands, hpi,cdi mini rotor,a massive 10w lighting coil :-) (led front lights en route) clutch shims,kick-start springs for the clutch(higher rpm grab). Hopefully it will be grab and go soon,this bit of kit is a tad above the level I was going, but what the hell,you only live once. Shame about the weather, test rides won't be until roads are dry and clear. All the grannies at the retirement home will love. Quote Link to comment Share on other sites More sharing options...
Hendrix's rifle Posted December 12, 2017 Report Share Posted December 12, 2017 Looks good that, get it on the road asap preferably on the snow it's always a laugh Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted December 14, 2017 Author Report Share Posted December 14, 2017 It rips up a treat,only problem is I have managed to pull one of the 6mm head stud threads,oh the joys,doesn't help being a hairy bottomed fitter. Quote Link to comment Share on other sites More sharing options...
pigeon controller Posted December 17, 2017 Report Share Posted December 17, 2017 These are the images of a Honda C90 that I found in a garage in Oropos, Greece. Lots of customisations... Quote Link to comment Share on other sites More sharing options...
Dunkield Posted December 18, 2017 Report Share Posted December 18, 2017 Nicely done, I assume there is a story behind the hand gear changer. Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted December 18, 2017 Author Report Share Posted December 18, 2017 15 hours ago, pigeon controller said: These are the images of a Honda C90 that I found in a garage in Oropos, Greece. Lots of customisations... They look well,hope mine will look half as good,I'm still sorting my power out,got it to a steady 45mph on the flat,waiting on a more suitable exhaust then I can try some different transmission fluid then tune my uprated clutch to the powerbond,change gear ratio, clean tank out,fit disc brakes,do some welding then paint. New lights,not very good,I only have 10w to play with,not getting a constant supply, I have fitted a regulator rectifier. Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted December 19, 2017 Author Report Share Posted December 19, 2017 I did it got to 50mph down hill,new exhaust, gearing, jets and clutch to sort next. Quote Link to comment Share on other sites More sharing options...
mel b3 Posted January 1, 2018 Report Share Posted January 1, 2018 Any more news on your build albert ?. Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted January 1, 2018 Author Report Share Posted January 1, 2018 I have since but another exhaust cut it in half and removed a baffle cone, welded it back together with the mig,that was hard work,changed the rear sprocket from a 45t to a 40, fixed 3 uprated clutch springs and set to grip at higher rpm,I managed to get 48mph on the flat and 55 downhill, since that I have been playing with the jetting, popping head gaskets and pulling head studs out. Im down to 40mph on the flat and it's starving itself of fuel. Carb is a dellortro phbg 17.5mm main jet 80 and pilot jet 40. I have never been able to open the air screw,hence dropping from a 50 pilot jet to a 40. I can now open the air screw,doing this scavanges fuel by suction from the bowl through the pilot jet not just relying on the main jet. I need to alter the float hight now. Also bored out my old 14mm Bing carb to 15.5mm just incase I can't tune this dellortro type one. Im currently waiting for larger jet for it. Hopefully pictures will show below. Quote Link to comment Share on other sites More sharing options...
Hendrix's rifle Posted January 2, 2018 Report Share Posted January 2, 2018 Good work that Quote Link to comment Share on other sites More sharing options...
mel b3 Posted January 2, 2018 Report Share Posted January 2, 2018 youre doing some fantastic work there albert, keep the pics coming mate. Quote Link to comment Share on other sites More sharing options...
Dunkield Posted February 11, 2018 Report Share Posted February 11, 2018 Come on @Albert 888 your groupies need an update Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted February 11, 2018 Author Report Share Posted February 11, 2018 OK,I have got to the point where anything I do isn't altering speed, I'm currently sourcing bits for a larger diameter carb- dellortro phbg 19mm, the one I have on is a phbg 17.5mm phbg copy, I have made a new intake manifold out of a bsp swept elbow to get better air flow but still no difference, the exhaust is now fully modified and sprayed with 650deg c paint, my max head temp is 370f around town around 30mph on the open road, I'm running at 310f wide open throttle , my plug chops show I'm lean at 1/3throttle 30mph, rich at full wot. I cut 12mm off the manifold end and now I have a wide powerband. Still only 48-50mph on the flat,my cylinder needs some serious port work, and clutch needs tuning also, currently engaging at 23lb of force,my timing is at 4mm btdc should be at 1.5mm but head temps are OK and my cdi retards at higher rpm. Quote Link to comment Share on other sites More sharing options...
TIGHTCHOKE Posted February 12, 2018 Report Share Posted February 12, 2018 This thread reminds me of Scotty on Startrek! " I've giv'n her all she's got captain, an' I canna' give her no more." Quote Link to comment Share on other sites More sharing options...
Dunkield Posted February 12, 2018 Report Share Posted February 12, 2018 Not sure if would help any, but is there any way the carb can be made to face forwards? Quote Link to comment Share on other sites More sharing options...
Gordon R Posted February 12, 2018 Report Share Posted February 12, 2018 It is a long time since I took a real interest in tuning and am a complete amateur, but I recall reading about the best way to tune the inlet. Popular theory was to make the inlet manifold as smooth as possible, so that petrol / air mixture could get in as quickly as possible. Latter theory suggested a roughened inlet gave better combustion, due to the swirl effect. I have seen devices which sit in the inlet to give that effect. Not sure how the OP could achieve this effect, if indeed he wants to do so, but it is a consideration, given that he appears to have hit a brick wall. Either way - good luck. I have really enjoyed the thread and admire the way the OP has continually tried something different. Quote Link to comment Share on other sites More sharing options...
Dunkield Posted February 12, 2018 Report Share Posted February 12, 2018 Same, advice seems to vary over the years, at one time fitting a slightly undersized gasket was one method to achieve this, but as you say common thinking is in/out as quick as possible. It was a whole lifetime ago, but the one thing I remember from the guy I went to college with who did this was he had a massive carb, taken from a kart if remember rightly? One of the challenges I would imagine is this isn't exactly a well trodden path Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted February 12, 2018 Author Report Share Posted February 12, 2018 Only a couple of mph to go. I need to I raise and widen the ports in the cylinder, if I pointed the carb forwards it would suck water dust and allsorts off the front tyre. The bigger carb that I'm still waiting for bits for will put me in the right direction I need to go. Home made air blade, came in a Box of bits I bought. Quote Link to comment Share on other sites More sharing options...
Jaymo Posted February 12, 2018 Report Share Posted February 12, 2018 With the carb facing the way it does your effectively creating a Venturi. That will lead to a drop in pressure in the inlet manifold which gives a decrease in density, hence your possible overly rich at the top end. either rotate or at the least get a filter on there to disrupt the flow. Must say, I’m no engine tuner though- just my experience of pressure and airflow. Quote Link to comment Share on other sites More sharing options...
Albert 888 Posted February 12, 2018 Author Report Share Posted February 12, 2018 It runs better without a filter,will try one on the 19mm one. Im slighty rich on purpose, I don't want to cook the piston or head,also running 60:1 premix . I have 3 jets in the phb,pilot 40, choke 50, and main 80. W7 needle 3Rd clip up. Temps are good I want to be in the high 300's f,not exceeding 400f. Needles and clips arrive tomorrow, so bigger carb more air flow,bigger jet and hopefully more mph. Quote Link to comment Share on other sites More sharing options...
Dunkield Posted February 12, 2018 Report Share Posted February 12, 2018 The reduction in flow from a genuine (not Chinese pod) K&N would be insignificant. David Vizard reckoned in some cases they can up the flow as they 'straighten' the air. I cringe when I see multi thousand pound engine builds running without any filters at all. Quote Link to comment Share on other sites More sharing options...
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