Forced induction 100cc

**husaberg** · 17th August 2012, 17:07

Originally Posted by Grumph

Okay, Hus, nothing I posted is in direct conflict with that lot....I'm advocating getting better exhaust flow with a better cam rather than using oversize exhaust valve. That lot reads like the author has a lot of sprinting experience - eg the Triumph info which is typical of the Brit sprint scene. Incidentally, I didn't see any reference to fuels though I didn't open any of the other attatchments. When using Methanol you must go to a higher percentage of exhaust flow vs the inlet anyway as the cooler/denser end gases flow slower.
This project is on petrol and end gas speed will be high. Yes, valve size is small. Without looking at the chink head i don't know if there's enough material spporting the seat ring to allow a larger valve safely - it WILL get f'n hot - particularly as it's horizontal. Easier and safer IMO to get the effect wanted with the cam.
Having been involved on the edges of a blown Triumph TQ - National Champ too - I disagree with some of the articles statements re those motors too....
Maybe I am just a grump but it's easy to put stuff up on the net if you don't have to back it up - not you Hus, the author.
I've been involved directly and indirectly with 3 blown TQ's and one roadrace bike plus several cars....all bar the roadrace bike were successful and the bike made the power but couldn't be made reliably raceable.

Monster Head 23mm and 27mm normally on the larger than 120's but not all Non Kawa based Chinky's

Most of the 110's more like this

A bit of a troll through here might give some idea of OE options for valves that may be more durable.
http://www.tkrj.co.jp/product/m-engine-valve.html

Almost forgot Honda are now producing a CRF110 so the parts quality may be higher.
She may be an oddball though.

Bore (mm/in) 50mm
Stroke (mm/in) 55.6mm
Displacement (cc/ci) 110cc
Compression Ratio 9.0:1

**Sketchy_Racer** · 17th August 2012, 17:10

My valves are 23 and 27 but can't really go any bigger, already had to relieve around the barrel for the intake valve (Not much thankfully)

The exhaust port tract is pretty short which is good to stop the exhaust heating the head.

**richban** · 17th August 2012, 17:13

Nice work on all of this Mate. Will be very interested in having a look at that injection system. Might be good for the FXR one day.

**Grumph** · 17th August 2012, 19:23

When you do have exhaust valve trouble - and i'm picking you will - don't faff about with OE valves. $50 gets you a top quality Ferrea stainless valve blank with 6mm stem. Either hone the OE guide or make and fit a bronze guide to suit. The bigger stem - I'm assuming the chinky is 5.0 or 5.5mm - will help with heat transfer without impeding flow to any great extent.
You never know, Richban may put in a good word with his bro to get you a discount....

**richban** · 17th August 2012, 19:33

Originally Posted by Grumph

When you do have exhaust valve trouble - and i'm picking you will - don't faff about with OE valves. $50 gets you a top quality Ferrea stainless valve blank with 6mm stem. Either hone the OE guide or make and fit a bronze guide to suit. The bigger stem - I'm assuming the chinky is 5.0 or 5.5mm - will help with heat transfer without impeding flow to any great extent.
You never know, Richban may put in a good word with his bro to get you a discount....

Already on the case if need be. Cam, valves whatever. I have a job for Glen so back scratching all round. We noticed on the FXR that the exhaust valve / seat was getting cooked. Looks like it wants more advance in the ignition. I guess it will be a balance act with the supercharged engine as well. Keeping enough of the bang in the cylinder to make the power verses getting it out and away from the valve to not eat the seats / valves. Kev says no overlap for the single.

**husaberg** · 17th August 2012, 19:38

Originally Posted by Grumph

When you do have exhaust valve trouble - and i'm picking you will - don't faff about with OE valves. $50 gets you a top quality Ferrea stainless valve blank with 6mm stem. Either hone the OE guide or make and fit a bronze guide to suit. The bigger stem - I'm assuming the chinky is 5.0 or 5.5mm - will help with heat transfer without impeding flow to any great extent.
You never know, Richban may put in a good word with his bro to get you a discount....

Good points mmm.. the cylinder studs will be pretty small too arn't they?

Originally Posted by richban

Already on the case if need be. Cam, valves whatever. I have a job for Glen so back scratching all round. We noticed on the FXR that the exhaust valve / seat was getting cooked. Looks like it wants more advance in the ignition. I guess it will be a balance act with the supercharged engine as well. Keeping enough of the bang in the cylinder to make the power verses getting it out and away from the valve to not eat the seats / valves. Kev says no overlap for the single.

**Sketchy_Racer** · 17th August 2012, 20:43

Originally Posted by richban

Nice work on all of this Mate. Will be very interested in having a look at that injection system. Might be good for the FXR one day.

Yeah mate, it's looking promising so far, but It's along way from being proven as an performance option. I have been surprised by the ease of integration on the kit onto my bike as it is a generic kit.

Originally Posted by Grumph

When you do have exhaust valve trouble - and i'm picking you will - don't faff about with OE valves. $50 gets you a top quality Ferrea stainless valve blank with 6mm stem. Either hone the OE guide or make and fit a bronze guide to suit. The bigger stem - I'm assuming the chinky is 5.0 or 5.5mm - will help with heat transfer without impeding flow to any great extent.
You never know, Richban may put in a good word with his bro to get you a discount....

Sweet I'll keep that in mind, I think we should start taking bets as to what will fail first, I recon the first point of failure will be the head lifting of the barrel, It has dowels in it but I think the studs will stretch at high cylinder pressure. We'll see.

Originally Posted by richban

Already on the case if need be. Cam, valves whatever. I have a job for Glen so back scratching all round. We noticed on the FXR that the exhaust valve / seat was getting cooked. Looks like it wants more advance in the ignition. I guess it will be a balance act with the supercharged engine as well. Keeping enough of the bang in the cylinder to make the power verses getting it out and away from the valve to not eat the seats / valves. Kev says no overlap for the single.

Yeah mate, once I get the motor running and the mechanics of it all sorted out I'll start hunting some HP. Reminds me, let me know when you want that Swingarm sorted.

-Sketchy

**richban** · 17th August 2012, 21:13

Originally Posted by Sketchy_Racer

Yeah mate, it's looking promising so far, but It's along way from being proven as an performance option. I have been surprised by the ease of integration on the kit onto my bike as it is a generic kit.

Yeah and for the money you just can go wrong. Just for all the electrics that a steel. Cost less than my FCR. I would probably go for a wide band gas sensor on mine with the Avgas and all. I spoz you can get sensors that will last quite a while on avgas these days. Yeah swing arm next week maybe. Also for the people that know about electric voodoo. Could you run a system like this without a battery. Capacitors or some other such thing.

**Sketchy_Racer** · 17th August 2012, 21:41

Originally Posted by richban

Yeah and for the money you just can go wrong. Just for all the electrics that a steel. Cost less than my FCR. I would probably go for a wide band gas sensor on mine with the Avgas and all. I spoz you can get sensors that will last quite a while on avgas these days. Yeah swing arm next week maybe. Also for the people that know about electric voodoo. Could you run a system like this without a battery. Capacitors or some other such thing.

Yeah if you had a charging circuit with a reg/rectifier you could run without a battery, Might just need to plug into something to fire it so the fuel pump can presurise the system.

As for the fuel pump it's the only part that I am not really that happy with and I can see it giving greif so I may get a late model intank fuel pump so it is all contained and the only hose I have is from the tank to the injector.

**Kickaha** · 17th August 2012, 21:52

Originally Posted by Sketchy_Racer

so I may get a late model intank fuel pump so it is all contained and the only hose I have is from the tank to the injector.

I might have one I can send you, I will check and let you know

**Sketchy_Racer** · 18th August 2012, 16:36

Originally Posted by Kickaha

I might have one I can send you, I will check and let you know

Awesome thanks mate.

Got a bit more done today, finished the plenum and trumpets etc, just need to get it welded up now. The trumpets are a bit of a dick design, but I want to be able to modify them so they bolt onto the plenum. I have also reviewed my plenum volume and it is now only 1000cc as I decided that the 1500cc may be to large for the little 100cc motor.

Once the plenum is welded all that leaves is the exhaust and blow off valve to sort and put the belt on the supercharger, oh and maybe improve the supercharge mount a little bit. Getting close.