Originally Posted by KHRacing

Jackojeff: Thanxs a lot for the kind advice.

125 is the goal. Im not doing any tuning, just buying the parts. my friend own a biketuning-shop with DynoJet rollers, he will be doing all the tuing.

Just so i understand you correctly. youré saying that i shall use the intake-cams on one engine & the HRC-cams on the other ?
Are both intake & exhaust cams from HRC "better" than the stock intake ?

Yes.. ECU is the same as CDI to me, in a car its called ECU & im used to cars :-)

Im really looking a true high topspeed on ice, but the rollingresistance (is that the word) is very very high on ic3 with spikes. But, CuldCutters wont work, they dont cope with such speeds at all.

A stock 180hp GSXR1000 just did220kmh last week testing, with 30mm spikes.
But he uses stock wheelsizes, i do think its waaay to wide for ice, there is a reason that rally cars only use 110-145wide snowtires for better grip. thats why im going for the cbr125 wheels :-)

Originally Posted by KHRacing

Jackojeff: Thanxs a lot for the kind advice.

125 is the goal. Im not doing any tuning, just buying the parts. my friend own a biketuning-shop with DynoJet rollers, he will be doing all the tuing.

Just so i understand you correctly. youré saying that i shall use the intake-cams on one engine & the HRC-cams on the other ?
Are both intake & exhaust cams from HRC "better" than the stock intake ?

Yes.. ECU is the same as CDI to me, in a car its called ECU & im used to cars :-)

Im really looking a true high topspeed on ice, but the rollingresistance (is that the word) is very very high on ic3 with spikes. But, CuldCutters wont work, they dont cope with such speeds at all.

A stock 180hp GSXR1000 just did220kmh last week testing, with 30mm spikes.
But he uses stock wheelsizes, i do think its waaay to wide for ice, there is a reason that rally cars only use 110-145wide snowtires for better grip. thats why im going for the cbr125 wheels :-)

Originally Posted by jackojeff

have been thinking about this for a few days and im scrapping what i said i reckon 125bhp is achievable

.........text.............

good luck

Originally Posted by KHRacing

+2mm overbore - more than 600,0 cc ? yes +1mm is still a legal 600cc as that is honda oversize, last i heard they stopped making the piston rings for +1mm here in the uk so maybe need to go to +0.75mm pistons for that slight edge

13:1 compression ratio - achievable easy with a skimmed head

38mm flatslide carbs - stock for now, mayby CBR954 carbs (929)
Kiehin FlatSlide 38mm carbs or dont change them, trust me on this one

gas flow - porting ? Yes polish and port

race exhaust - where do i get one for such an old bike ? No idea to be honest, i managed to scavange 2 together here in the uk, does sweden have a club racing series? maybe a steel frame championship ask them or my HRC manual has a DIY HRC one in it

remove magneto and stator - for less friktion, less moving parts ?
Removing the magneto and stator allows for the engine to spin up a lot quicker than standard and removes engine breaking to a point were it rides like a 2 stroke with a 4 stroke power delivery if you understand

remove clutch backlash gear - dont know what this is ?
getting me to share all my racing secrets here haha on your clutch there are 2 gears basically riveted together there are also 4 springs,

one is red you remove that and then you can leave the thin plate in or you have 2 other choices

1. remove the plate and have it machine riveted back together
2. you just mill the plate down slightly for less rotational mass

this modification will make the bike spin up quicker again but will make the clutch a little more snappy hey if you have clutch control you wont have an issue

colder plugs - no problem
dont do that until you have had it on the dyno and seen what its putting out and how hot it runs, the colder plugs are meant to stop pre-ignition in the cylinder if your not running hot enough it wont work
honda air filter with paper element removed (gauze filter) thinking of runing on the ice without airfilter. must be the best. no resistance, no foreign parts except iceparticles
erm other than a stud coming out of a tyre or another bolt/part off another vehicle i cant see why not, it will run a lot more air through the system and be no need for a bigger ram air then

hrc cams - yes

remove air solenoid - is this the small tubes from the small intakes in the front ? yes there are loads of tubes that then go into the carbs remove them all and re-tube it like i have on the picture i will link

cut back the ram air vent or even better make a bigger ram air box (2 litres bigger)- this ill take a look at tomorrow see above or google there was a company in the uk that put a bigger carbon fibre air box on with flatslide 38mm carbs and a few other tricks and pulled 115bhp

bigger radiator . i have a handmade racing radiator.

Originally Posted by Burnt Dragon

Hey Folks! Now this is a super interesting thread. To make that kind of power out of a small displacement engine I'm sure is not impossible and I can't wait to see the results on that engine build.

What's even more interesting to me is the speeds you're aiming for on ice. I was wondering to myself (don't get me wrong, I know it's been done), tire stability? Now before anyone gets upset, I think about this when flying down a back paved road on my dirt bike on the way to a bush trail... (these wheels aren't balanced, tires aren't rated for these speeds, never mind spokes?) when will these tire carcasses blow apart?

I'm sure you're on to me by now...
Street bike tires are rated for maximum speeds as follows:

Rating F J L M P R S H V Z W (W)
MPH 50 62 75 81 93 106 112 130 150 150+ 167 167+
KM/H 80 100 120 130 150 170 180 210 240 240+ 270 270+

So if my tires are constructed in such a way as to handle whatever forces that are applied to it at such a speed, how does modifying that construction effect the ability to withstand coming apart (ie; punching several holes, adding weight at each one of those holes)? How do you now rate or de-rate your tire?

The only experience I've had relating to these tire limits is when hauling a bike trailer at a speed beyond the tire rating. The tread peeled right off of the steel belting like it was filleted like a fish!

I would love to hear what you all think. Did I raise a decent question? What do you think KHRacing? As for me, I wouldn't have the nuts! LOL!