as the title suggests.. i have undertaken this small project.. so far i have made my bike partially ready.. here is what i have done so far..
1:installed a 4 wheeler Cylinder of 107cc capacity
2: and a corresponding Cylinder head..
both the things were just bolt on fit.. no new timing chain was needed..
i also upgraded to an after market china carburettor that comes for qingqi 100cc rickshaw.. did nothing to the jets ..mixture is a bit rich but proper setting is needed.current jets are unlabelled. however from spark plug reading mixture is in acceptable range...
So far results are quite decent...pick is increased . very much..it reaches speeds of 80 in fairly short time..top speed is 90 but it severely vibrates past or close to speeds at 80. current sprockets are 14/41 default..
the new 110cc head is exactly the same as of the chonda 70 only difference is the size of combustion chamber which is slightly enlarged for the 52.4mm cylinder as opposed to the 48mm chamber of chonda 70.. The intake valve is 23mm and the exhaust valve is 20 mm.same values as of default cylinder head of dhoom 70. silencer is the same old of dhoom 70..
Now i need suggestions/verifications as to what should i do to make it a bit faster.. in-fact not faster but to make the gears longer as at speeds above 60 (definitely in 4th gear) it seems as if it needs to be shifted to next gear..
Now, one mechanic suggested me to use the following
1: qinqgi clutch gear..and he said it costs 800-900 rs in new.. DONE
2: and also to upgrade to 3 discs/plates clutch boxa...( infer for yourself
what he meant.) DONE
3:someone also suggested me to open the ports ( portain khuli kara lain) [To be done]
4: replace the paper type filter element with a foam type ,, [To be done]
will make a video about the project on what i have done so far.. in a couple of days. and rearrange this thread..
also suggest a good mechanic..in pindi islamabad..
Some pics of the new cylinder head (110cc)
This is the combustion chamber of 110cc cylinder..
Following pic show the scale next to the centre line of a 110cc combustion chamber ..my readings using vernier scale were as follows.
the inner circle is of 40mm dia same as in dhoom 70 chamber
the outer is of 52mm dia , 4mm bigger then the chamber of dhoom 70
depth is same for both..at the center line..
vernier calliper showing the outer dia.
110cc cylinder installed.. along with a piston. the piston was partially seized but the mechanic who installed it said it is ok.. many mechanics also said so.. however rings were new. of STR.. the rings which i bought were for 150 rs and they were of zero number from united 100cc bike..(that bike in reality is a 110cc)
Piston at BDC of the cylinder.
another view of piston at BDC .
Piston at TDC. not the piston was flat shaped but there was too much compression.. so we tapper cut the piston.. that's why the piston looks pretty old at centre and clean at the edge... this pic was take after this piston did some 20 Km ...
Another View of Piston at TDC,
Picture of Exhaust port from cylinder head.. no silencer installed yet..
another view of the exhaust port of the cylinder , silence isn't installed yet..