SS1600K attempt on a 90cc Postie

Ziggy

Just Another Rider
Premier Member
IBR Finisher
#21
Thank's for the update Karl, Pleased Dave is ok

Was hoping wishing and pushing him along for this one... He's spent a lot of time getting this ready.... and I'm sure and believe he will do it one day.

Good luck and all the best for the next run.
 

Tele

Premier Member
#22
Truly awesome effort on such a bike .... pleased he was able to recover from this and ride the poor beast home .
Very best wishes for the next attempt
 

OX-34

Premier Member
IBR Finisher
#23
...........
Hello All,

Today I will be attempting a SS1610k ride on a 1999 Honda CT110 (postie bike)...............

This ride has been done on a 110cc postie bike by a fellow FarRider already, he finished in around 23.5hrs with an overall average (OA) of 70.?Km/hr. .................

Frog (Dave)
I'm sure you'll get there on the next attempt Frog. Bugger about that tyre.

Here's the screenshot from the ride on my (105cc) Honda CT110:





 

Frog

Premier Member
IBA Member
#24
Thanks for the interest, I will be attempting my greatest challenge yet... A RIDE REPORT:eek:. I like to think of myself as a Rider foremost and a Writer not so good. This I will express a view on later. So once again thankyou for watching and I will post soon.
 

brodes

Active Member
#25
Just catching up on all this. Great stuff Frog, good to hear you are OK after the stack, looking forward to the ride report
 

Frog

Premier Member
IBA Member
#26
It looks like the weather will be favourable (not a 25km head wind) on Monday/Tuesday for an other shot with Tadpole at the 1600. whilst it was a flatty that stopped the show last time I felt compelled to fix a couple of little things that have been nagging me see pic. IMG_20160118_135017_632.jpg
and it didn't stop there...
guts.jpg
 

Frog

Premier Member
IBA Member
#31
here are some of the things that were annoying me. The mighty best drank 650ml of oil over the 1200km run. a little via heavy breathing but most burnt. first mission change the engine breather from 6mm to 10mm (pics below) this will mean that the same volume of crank case air passing through will have a lower velocity thus not carrying as much oil. the cranking pressure is 170-175psi so I don't think it is getting past the rings and pressurising the case.
old breather.jpg

new breather.jpg
 

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Frog

Premier Member
IBA Member
#32
next, burning oil. now this little engine was the butt of a joke at some stage. When I rescued it from under a tree and stripped it I found a wood screw imbedded in the piston. as a consequence the inlet valve was bent and seat damaged. new valve and seat repair think no more. now Taddy holds 900ml of oil so using about a litre for the 1600km is no biggy cause I carry two litres... but have a look at these pics
DSCN0506.JPG
DSCN0512.JPG
here is the piston not quite finished machining it to get 10.3 : 1 CR and very good valve clearance.
piston.jpg
you will notice that the carbon from the burnt oil has filled the valve ports and lined the combustion chamber this will have raised the CR well towards or past 11 : 1 CR. I think 11 : 1 is really pushing it on 98ron in a hot little air cooled motor. To give an idea the final cut on the crown of this piston was 0.6mm witch dropped the CR from 10.8 to 10.3 so you can see how the carbon deposits increase the CR.
These are not very good pics but believe me there has been a bit of detonation due to the increased CR and the piston, chamber and edge of the copper head gasket are showing signs of erosion.
Now, detonation will cause the compression rings not to seal in the bore and increase crank case blow by not to mention engine meltdown. this event would be categorised as a walk, not a SS or BB.
 

Frog

Premier Member
IBA Member
#33
So nothing for it but new valve guides, the only other way Taddy could be sneaking a sip of oil. But it isn't that easy. first we strip the head, then when Warty isn't looking heat the head to 150C in the oven and gentle tap the guides out...now I have samples. CT90's and 110's for that matter, have only a valve guide seal on the exhaust side. The theory is that being a near horizontal engine with the inlet at the top of the head, the oil pools at the bottom around the exhaust valve so no oil will get sucked down the inlet only find its way down the pressurized exhaust stem? maybe it is to prevent the oil filling the pot when the engine is stopped?
Any way the later CT110's have a real guide seal, just like real motor bikes...but still only on the exhaust. below are pics of what one can do with a micrometre, lathe and some time in the wee small hours. the new guides have a shoulder below the seal to stop the inner spring chafing the seal. the 110 springs are bigger ID to clear the seal so I had to change to 110 springs and collet retainers which resulted in the CT90 rocker arms fouling on the retainers... a bit more machining.
guides.pdf
stopping the oil will also give a small boost to the power
 

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Frog

Premier Member
IBA Member
#34
So here I am now dialling the inlet cam lobe centre. which means I am just about ready to light the candle:). I have slotted the cam flange to achieve this and have it set at 102.5 deg. this is from much trial and error the spot I once recorded several 8.7 RWHP runs on the Dyno. I may pull the alternator cover off and slot the CDI trigger sensor to change the IGN timing but that would probably mean missing the next window on the weather:oops:
Dialing the cam.jpg
 

Frog

Premier Member
IBA Member
#35
I also put new mains and a new rod bearing in it, just thought there was a little rumble in the bottom at idle. Here it is pressed back together with 1/2 a thou run out at the end of the shaft:D very happy with that.
crank run out.jpg
 

OX-34

Premier Member
IBR Finisher
#36
Crikey! I just bought my 105cc Postie from ebay and rode it twice as a warm up to the SS1600. I put in 50ccs of oil during the run.

This build / rebuild is incredible Frog. Just a couple of days to go for this weather window.

Good luck on Taddy.
 

Frog

Premier Member
IBA Member
#37
OX-34Premier MemberIBR Finisher
Crikey! I just bought my 105cc Postie from ebay and rode it twice as a warm up to the SS1600. I put in 50ccs of oil during the run.

This build / rebuild is incredible Frog. Just a couple of days to go for this weather window.

Good luck on Taddy.

About that window....
I thought I might play with the gearing, can't buy what I want..... 44Tooth.jpg
so make something else fit.;)
 
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Frog

Premier Member
IBA Member
#38
when pushing something to the limit there are side affects, that's why top fuel engines only survive a few passes.
This whole 90cc thing is just an experiment to gain experience/ Data for the next project. I was originally tempted to do it on a 110cc but since OX already did that in 23 and a bit hours (thanks for doing that test for me) I figured that that size bike wasn't small enough and I needed one that wouldn't do the SS1610 without major modifications and the challenges that come with the build.
Once this run is successful I will have a frame that I can fit 5occ - 140cc engines in without having to re- farkle each time, and once used to the riding position it will only be a change in power to get used to.
My ultimate goal is what I will call a "Laurel and Hardy" back to back.
 

Skidoo

Premier Member
#40
Frog, you certainly get involved with your rides from design, fabrication, testing, execution and redevelopment. Mate; its a pleasure to watch your progress and looking forward to enjoying your success :)