Engine project

Show us that box of bits in your shed!
stevo135+
Smoker
Posts: 58
Joined: Tue Sep 01, 2015 1:23 pm

Re: Engine project

Post by stevo135+ »

Don't two strokes generally run hotter like for like than four stroke engines though? Again I don't know much, but I always thought the extra two strokes in a four stroke engine allow it to shed alot of the heat between power strokes?

I can understand high exhaust gas and cylinder head temperatures when you start playing with turbocharged petrol and diesel engines though.
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Re: Engine project

Post by Luders »

You start losing bhp if a 2-stroke engine runs too warm, so it's best keeping them as cool as possible.

Coolant in a 4-stroke can get in excess of 100°C, whereas a 2-stroke would be totally cooked at those kind of temperatures.

Coolant in mine runs between 56°C - 58°C with exhaust gas at just under or around 600°C
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Re: Engine project

Post by Luders »

JanBros wrote:a better way to get more heat in the pipe to get more overrev , is to reduce the spark energy when the power starts to drop. But I don't think a Zeel can do that ?
Borut makes a model with programmable spark power, which is what I run in my bike Jan.
User avatar
scooble
Premix Junkie
Posts: 1549
Joined: Thu Jul 27, 2006 12:47 pm
Location: West Sussex
Contact:

Re: Engine project

Post by scooble »

although two stroke engines fire twice as many times as four stroke engines, I believe they also run cooler. Having used Exhaust Gas Recirculation to control Nox, the result is slightly lower exhaust temperatures and I suspect the same principle also applies to two stroke engines with the slightly diluted fresh charge
User avatar
500bernie
Avgas Sniffer
Posts: 3396
Joined: Mon Aug 02, 2010 10:22 am
Location: Teesside

Re: Engine project

Post by 500bernie »

Hi Doug,
It looks like you had a great time with Mick 8)
He is a true gent and a genuine enthusiast, I always call in whenever I am passing (Us Smoggys stick together).

I keep promising, but I have never gotten around to letting Mick work his magic on my 300.......yet

Cheers,
Bernie :)
Firecracker Red and Grey C3 300
DougB
Oil Injector
Posts: 590
Joined: Thu Dec 12, 2013 9:58 pm
Location: York

Re: Engine project

Post by DougB »

Now then Bernie, we did mention you and the 300 :wink: told him a couple of bits on mine had found their way down from you.

Mick is moving back up to Smoggy land in the next month or so, said he'll be living back near you so no reason not to nip along and strap the bike bike down for a few runs :lol: :lol:

Didn't realise his workshop was in Starbeck, I practically drive past every day, and now I've found out he's packing up and heading away! Guess if I'm heading up your way to Micks for testing might I finally get a chance to see your twins..

Cheers.
User avatar
500bernie
Avgas Sniffer
Posts: 3396
Joined: Mon Aug 02, 2010 10:22 am
Location: Teesside

Re: Engine project

Post by 500bernie »

Hi Doug
Well that is great news for me, I hope the access to his new place is a bit more conventional.
There is always an open invitation to any Kr fan to drop in for a cuppa at my place.
Just give me a shout to make sure that I will be at home.
Cheers
Bernie :)
Firecracker Red and Grey C3 300
DougB
Oil Injector
Posts: 590
Joined: Thu Dec 12, 2013 9:58 pm
Location: York

Re: Engine project

Post by DougB »

Not Happy!!!! Bl@#dy pattern parts let me down yet again. Don't know why I keep falling for the ads and recommendations.

Needing a clutch I ordered the steel plates from Kawasaki then realised they do the 5 friction plates but don't do the 6th thin friction plate any more. I was recommended to use a Walker clutch, said it was a good quality kit with all 6 plates so I figured jobs a good 'un! It wasn't. Arrived today, all 6 plates identical (they haven't even realised one has to be different) and then they don't fit either as the drive tabs are too long so they hit the outer clutch casing :evil: :evil: Enough said it's going straight back.

Now I've got the 5 standard plates on order from Cradley and figure I'll have to re-use the end plate, but I doubt I'll get the parts before the weekend so that's a big set back. TT soon so very little chance to get back to Mick and get any dyno testing done before I go. I was hoping to have the clutch on for Sat and just squeeze in a visit by mid next week.

Crappy rubbish waste of bloody time!!!
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Re: Engine project

Post by Luders »

Cradley are pretty good if you ordered them yesterday. What did they say the expected delivery would be. What's wrong with the ones you had? It's the friction plates that normally cause issues with clutch slippage and having tuned the engine, you always need to uprate the springs.
User avatar
scooble
Premix Junkie
Posts: 1549
Joined: Thu Jul 27, 2006 12:47 pm
Location: West Sussex
Contact:

Re: Engine project

Post by scooble »

I got uprated EBC springs in mine and never had any problem, but then again, its never put out more than 51hp!
DougB
Oil Injector
Posts: 590
Joined: Thu Dec 12, 2013 9:58 pm
Location: York

Re: Engine project

Post by DougB »

Hi Scooble, I think i might've got away with the Dyno if I'd put stronger springs in.

Ben, I took the whole lot apart and measured the friction plates and they're on the limit about 2.7mm so I def need to change them, but I figured new steel plates and springs wouldn't hurt either (now I know it really should've had new springs in before hand!) Anyways new springs and steel plates I ordered at the start of the week have just arrived from Cradleys today.

I ordered new friction plates from Cradleys last night so I'm sort of keeping fingers crossed they might arrive by Saturday. Pic of the Walkers tat:

This is a new plate layed onto the old one:
Image

New plate in the basket:
Image
User avatar
Top-shaggy
Premix Junkie
Posts: 1966
Joined: Mon Oct 31, 2011 11:09 pm
Location: Derbyshire

Re: Engine project

Post by Top-shaggy »

The smaller friction plate is still available at CMSNL

http://www.cmsnl.com/1991-c3-kr250_mode ... 0df8ny9KK0
If it takes more than 2strokes then your just playing at it..
Luders
Avgas Sniffer
Posts: 3926
Joined: Fri Jun 18, 2010 11:29 am
Location: Oxfordshire

Re: Engine project

Post by Luders »

Get some heavy duty EBC springs, not OEM ones. Have a look on ebay.
DougB
Oil Injector
Posts: 590
Joined: Thu Dec 12, 2013 9:58 pm
Location: York

Re: Engine project

Post by DougB »

Ah well I ordered friction plates from Cradleys and the heavier "R" springs that were mentioned earlier, unfortunately when I ordered the website said in stock but it turns out they weren't and are coming from Holland so springs and plates will likely arrive Tuesday ish (shame, if I'd know I would've just ordered the plates and probably had them by now as they were on the shelf).

When it's all done I'll see if new steel plates/friction plates and springs have been enough to sort it. If not a friend of mine runs Yambits which isn't too far from Mick Abbeys so as a last resort I could nip and raid his EBC stock and see if I can get some of them HD springs.

Going to be very tight to get anything done before TT race week so every chance it'll be mid June now, see how it goes.
DougB
Oil Injector
Posts: 590
Joined: Thu Dec 12, 2013 9:58 pm
Location: York

Re: Engine project

Post by DougB »

Top-shaggy wrote:The smaller friction plate is still available at CMSNL

http://www.cmsnl.com/1991-c3-kr250_mode ... 0df8ny9KK0

Hadn't spotted that, thanks for the link.. got one ordered :-)
Post Reply