Nemett Lynx 15 cc 4 Stroke I/C Petrol Engine

[Jasonb]

Yes two magnets; as you are using a CDI the timing delay will be wrong as it will think you are going half speed. CDI's have no concept of revs. They only know about time intervals and need to know how long it is going to take for the crank to move from the trigger point to the TDC. With the camshaft going at half speed it takes twice as long and the firing point is then late.

Pete

Not quite true for all CDIs, only applies to ones with auto timing, if you use one from the likes of S/S it will only need a single magnet on the cam as it does not need to know how fast the engine is running and saves wasting a spark.

J

 

[doubletop]

Not quite true for all CDIs, only applies to ones with auto timing, if you use one from the likes of S/S it will only need a single magnet on the cam as it does not need to know how fast the engine is running and saves wasting a spark.

J

Jason

Thanks for helping to avoid confusion but Gus was asking about using an Rcxel ignition which does do auto timing

Pete

 

[Swifty]

Gus, I know that you have been having a bit of a break, but any longer and you will forget where you got to. I'm keen to see your engine running, as I'm sure others are.

I've been having a rest myself after finishing my Lynx, haven't started any other projects yet, but it's still amazing that I manage to fill the days in.

Paul.

 

[fishy-steve]

I'm with you Paul.
Pull your finger out Gus!!!
We need to see this engine running.

Steve.

 

[Brian Rupnow]

Gus--I have the feeling that something has gone wrong over there. I hope your health is good, and I hope that if you are suffering from "Machinist burn-out" that some time away from model engineering will fix that. Please let us know what is happening. --We worry about you when we don't hear from you.---Brian

 

[Swifty]

I think that Gus is away fishing for a while.

Paul.

 

[fishy-steve]

If that's the case then Gus really sounds like my type of guy!

 

[gus]

Gus--I have the feeling that something has gone wrong over there. I hope your health is good, and I hope that if you are suffering from "Machinist burn-out" that some time away from model engineering will fix that. Please let us know what is happening. --We worry about you when we don't hear from you.---Brian

Hi Brian and Paul

No worry. Gus just got back after a week of great fishing in Kuching,Sarawak---land of head hunters hundreds of years ago. The ''
Native Dyak'' head hunters missed Gus and so my head is still intact. Three days fishing. First day was bad. Second was also (bad) with non-stop fishing. Six big fish out of ten drops. Third day gave up my spot to the trip leader.See foto. My darling wife is so happy with the Red Snappers and we will have quite a few rounds of Curry Fish Heads for dinners.
Now busy extracting the lazy bones. Nemett-Lynx engine should be up and running this week.

 

[gus]

Alrighty. Gus on the saddle now with lazy bones totally removed.
Here's my Hit List.
1. Make base c/w Formica.(Done 11 am 20th Oct ,see foto)
(Exotic hardwood very expensive here. Use surplus Marine Plywood)

2. Fuel tank.( Blank Fuel Tank done/capped both ends today at 5pm 20th Oct.) ( Gas tank mounted on. Work on schedule as promised. 21st Oct 4:30pm)

3. Cranking device as per Paul's

4. Hall Effect Adapter

5. Tune up all timing, cams , valves and igniting.

6, Run.

Will report progress. However Gus has to have his right eye checked today to confirm cataract ripe for operation next month. So best to get engine spinning.

 

[gus]

If that's the case then Gus really sounds like my type of guy!

Hi FishySteve,

Are you an angler too??
You are welcomed on to my boat,if you visit Singapore. Gus has too many hobbies and so little time. It is true when engines get too tough to make,I do get burnt out and hence need to rest/switch my brains to do something else but engines. Carpentry and fishing are good escape venues.

Take care.

 

[fishy-steve]

Hi FishySteve,

Are you an angler too??
You are welcomed on to my boat,if you visit Singapore. Gus has too many hobbies and so little time. It is true when engines get too tough to make,I do get burnt out and hence need to rest/switch my brains to do something else but engines. Carpentry and fishing are good escape venues.

Take care.

Hi Gus.
I do indeed fish. Mostly flyfishing for trout on inland lakes and rivers.
On my list of things to do is a visit to Singapore for the Grand Prix.
Steve.

 

[gus]

Gus been doing carpentry for too long. Tried a mixed of carpentry and metal bashing and came up with a clip bending jig in 5 mins. Its a must to anneal brass strip for easy hand bending.
The last all metal bender gone with the wind.

 

[gus]

At last my engine is all prepped to run early next week. The Hall Effect Sensor probe not done yet.
Timing all done .Compression good but whether its good enough to ignite and run.


Fuel Tank and mounting clips are very much a borrowed invention from Paul.
Thanks .Paul. IOU beers.

 

[Swifty]

Gus, I did mention in another topic where you had posted a picture of the fuel tank, be careful, it may be a bit low. The fuel has to be sucked up a fair way, if it can suck up this far, you may need a non return valve. Just my first thoughts.

I'm getting excited to see it running, it looks as though it ready, don't tell us that you are going fishing again this weekend

Paul.

 

[Swifty]

Gus, you asked about the prop on another topic, I decided that I would reply here to keep it all neat. The prop I have is 15" dia x 5" pitch. The pitch is not important as it is only for display, I found that the prop is too light to keep the engine running, perhaps with a bit of loosening up it may be ok, or maybe I can make a heavier prop drive to give it some weight. I searched all over ebay for a prop, but finally found a suitable one at a hobby shop nearby for A$20.

Paul.

 

[gus]

Gus, you asked about the prop on another topic, I decided that I would reply here to keep it all neat. The prop I have is 15" dia x 5" pitch. The pitch is not important as it is only for display, I found that the prop is too light to keep the engine running, perhaps with a bit of loosening up it may be ok, or maybe I can make a heavier prop drive to give it some weight. I searched all over ebay for a prop, but finally found a suitable one at a hobby shop nearby for A$20.

Paul.

Thanks for the info.Will shop for a 15'' prop.

Or I might make a stubby prop out of pinewood just for fun. Will be very relaxing DIY prop. My spokeshaving skill is junk. Will take this opportunity to practice and improve this skill.

OK .Told my fishy mate,too tired to fish tomorrow. Will try spinning engine tomorrow.

 

[doubletop]

I'm using a 16"x6" from HobbyKing.

http://www.hobbyking.com/hobbyking/store/index.asp

I was interested to hear of Swifty's experiences with a prop and a flywheel which makes me think of trying a flywheel at some time.

Pete

 

[gus]

Paul gave me good advice. The fuel tank is a wee bitty low and best to put in a check valve to prevent gas flowing back to tank.
OK .Done . Recycled check valve from H&M Engine. No fishing today. Coming to the very last item. Adapter for the Hall Effect Sensor. Will be done by 5pm today.
No fishing today. Spent the morning mopping up and recuperating from the after effects of SeaSick Pills.Must have been a new brand not good for Gus.

 

[gus]

Went shopping for 14'' prop. Cost me S$10. or A$8.00.''Scimitar Profile Master Airscrew.''
Cutting my DIY prop will be too labour intensive/time consuming.

 

[gus]

Day One.
All rigged up. Getting very good compression but CDL not firing. Spark Plug have not sparks.

SOS. Is magnet strength and polarity of magnet important?? Distance gap between magnet and Hall Sensor important?