New Hawk, new adventures.

[TxTaoRider]

Originally Posted by Megadan

So, it did get a bit colder than predicted by our phenomenally accurate weather people and it ended up being closer to a 30 degree drop (I was really cold on the way home) so I am going to hold off on judging any potential fueling changes until I can ride it in near similar air temps.

As far as noise reduction goes. From what I can tell this particular quiet insert took my high compression, advanced timing, cammed - obnoxiously loud exhaust back down to standard ebay muffler on a standard hawk levels of volume. I find it liveable. If the fueling is not too greatly affected - say the 130 main jet works out well with it, I can live with that. Maybe I am sacrificing half a HP on the extreme top end, who knows, but the bike is still immensely strong on the low and mid range. Even with the 17/45 equivalent gearing it just feels like a stump puller.

Side note. thanks to some help I put an order in on an aircooled CG300 cylinder and piston kit from Aliexpress, so the previously attempted and abandoned "big bore" CG is back on. Not likely to be a project I will attempt this year, but I want to get the parts together.

Do you have the link to the 300cc kit?

[Megadan]

Originally Posted by TxTaoRider

Do you have the link to the 300cc kit?

I sent you a reply in your messages

[Megadan]

So, got my headlight bucket in at least. Still waiting on the brackets and I need to order the projector and related bits still, so it will be a bit longer until I can complete it, but this is what it will look like.

Thankfully, this bigger style of bucket houses the entire projector housing assembly rather well. Has a little room to spare on the inside.

As somebody else put it, looks a bit like something out of Star Wars lol.




The spaces between the ribs being open is making me consider putting a 12v strip of LEDs around the inside and wiring that in to the DRL light, which in typical Hawk fashion only turns on with the headlight.

[JerryHawk250]

That will be a nice upgrade. I had rewired my DRL light to come on with the ignition.

[Megadan]

Originally Posted by JerryHawk250

That will be a nice upgrade. I had rewired my DRL light to come on with the ignition.

It's not really necessary as an upgrade, but I figure if I am going to do it, might as well be silly about it. 2800 actual lumens from a proper high power chipset. Still less wattage than the original 35w halogen to boot.

I am undecided on what to do with my drl circuit yet. I may add a demon eye light to the projector and rewire it as you did.

[China Rider 27]

You should do a beam comparison like they do on flashlight tests, LED against whatever that monster is.....

[Megadan]

Originally Posted by China Rider 27

You should do a beam comparison like they do on flashlight tests, LED against whatever that monster is.....

That monster is LED lol. I could do before and after of my Hawk with it's current plug and play LED like most of us have vs. This guy. It would be hard to do it any real justice without being able to fix/lock the exposure though.

[Megadan]

Three attempts over several months and finally I got my hands on one. Even came with a steel head gasket.



So, the only catch to the CG300 cylinder is that the outer diameter of the sleeve at the engine cases is a tiny bit too big, so some sort of machining needs to be done. Roughly about half a mm needs to be removed (I will measure when I can) from the outside of the sleeve to match a CG250 cylinder, so instead of machining the cases I think I am going to do it the "wrong" way and remove from the outside of the sleeve. I don't think a couple thousandths are going to hurt anything.

I also don't plan on installing this anytime soon anyway as I am considering changing to a different cam style with some added lift, which will means I need to have more head work done to recess the valve seats for valve clearance reasons. So this is likely going to be a winter project.

[TxTaoRider]

I wonder what the compression ratio will end up at. It's a much bigger displacement with a flat top piston under the same cc head.

[Megadan]

Originally Posted by TxTaoRider

I wonder what the compression ratio will end up at. It's a much bigger displacement with a flat top piston under the same cc head.

That is another reason I am not going to just slap it together, but I doubt the compression ratio will actually change very much. I am going to compare the cylinders and pistons to my CG250 parts sitting in a box, measuring crown height, compression height, and I may even find a way to measure piston Dome CC of the 250 piston. I know it isn't very much though. Plus, a larger bore, with no other changes to said piston, compression height, etc, actually increases compression, so the loss of the minor dome of the 250 piston may well balance that out if all other factors are equal.

A part of me is tempted to, assuming my measurements confirm the above speculation, simply install the cylinder with my current head and cam setup. A part of me is curious to see if my already ridiculous midrange and low end torque will become the ultimate in tractor pulling power lol.

[TxTaoRider]

If you cc the head, mock up the assembly for deck height, etc and find the CR is gonna be too high (who wants to run 100+ octane in a daily playbike?) you might be able to find a shop that works on modded two strokes and have the squish ring area machined some. The 4 degree ignition key way may have to go too. But for the extra displacement it should be worth it.

What will the actual displacement work out to?

[Megadan]

Originally Posted by TxTaoRider

If you cc the head, mock up the assembly for deck height, etc and find the CR is gonna be too high (who wants to run 100+ octane in a daily playbike?) you might be able to find a shop that works on modded two strokes and have the squish ring area machined some. The 4 degree ignition key way may have to go too. But for the extra displacement it should be worth it.

What will the actual displacement work out to?

The person that shared the source for this cylinder set is already running one on his bike, also with a cam and decked/ported head. So it's not likely much different at all.

Actual displacement would be 250.149cc (65mm stroke x 70mm bore). So it will be an actual 250cc lol.

[TxTaoRider]

It's still a 9% increase in displacement which on a head flow restricted motor like the CG may not add any hp, but it will pump up the torque.

On the BB kits for the KTM rfs motors, some of the guys complain they lost a little rpm over rev, but after you adjust your riding style it's a win. Of course we used to have a bunch of cams we could use to make up for the overrev if we wanted. The cg cams are a little more limited in selection.

I cant wait to see how it works.

[Wild Dog]

Yeah the "right" way to do it, is machining the case. To be honest, is not worth doing it. A modded Hawk like the way dan is, can already beat a stock "300"

Originally Posted by TxTaoRider

It's still a 9% increase in displacement which on a head flow restricted motor like the CG may not add any hp, but it will pump up the torque.

On the BB kits for the KTM rfs motors, some of the guys complain they lost a little rpm over rev, but after you adjust your riding style it's a win. Of course we used to have a bunch of cams we could use to make up for the overrev if we wanted. The cg cams are a little more limited in selection.

I cant wait to see how it works.

That's exactly what they do went go bigger on the CG, more torque. That's why a stock 200cc will have similar top speed than a 230cc.

The picture above is the "GATO CG300" it has the same top speed than a 230 but it's more torquey

About the cams you would be surprised about all the differents profiles they made for the CG. To be point of being ridiculous

[TxTaoRider]

I ordered one of the kits but wont make any efforts to install it until this summer when it's too hot to ride here.

For now I'm messing with suspension.