copelab

Bisson is not the pitts,just a .60 size type.
Bob

copelab

Well,another unsuccessful day.Flight #1 set for about 10.3k,and ran fine for the nine minute flight. Second flight went deadstick after which it started running like crap again. Noticed there were a lot of bubbles coming out from around the idle disc. I removed the disc and found the grey gasket had several pieces out of it an it was torn.So I figure that or the o rings are causing the problem. The engine is going back in the box for now. At least the DX8 worked.The motor aslo felt a lot cooler on the 1st flight and hot on the 2nd. Guess it went lean.
Bob

1QwkSport2.5r

Those O-rings on the idle disc are crucial to the engine running properly. You can get replacements at the hardware store. No wonder it wasn't running right!!

copelab

Pretty small o-rings. Home Depot do you think?

spaceworm

Or Ace Hardware or True Value. Look in the small hardware bins or in the plumbing supplies. Best would be silicone or Viton, but not likely at either of the proceeding. Try an automotive parts store for them. Or Macmaster Carr. Good luck.

1QwkSport2.5r

Mom and pop hardware stores, ace hardware, or if you're lucky Menarda/Home Depot/Lowes. When I replaced the o-rings in my K&B carbs, I found one size at Menards and one size at a local mom & pop hardware store. $.10 each. If you need the sizes, I can measure the o-rings on one of my carbs.

Dont bother trying to get parts from Mecoa (current K&B manufacturer).. You might not get your order for a month if at all.

copelab

Thanks;it would be nice to know the proper sizes.Sounds as if they are two different sizes. I found a couple of 3/16 o-rings in my stock but they do not seem to fit well.
Bob

SRQFlyer

My Feedback: (17)

I bought 50 of each of the 2 sizes necessary. PM me your address and I'll send you some.
Jim

copelab

P.M. sent.Thanks Jim.
Bob

earlwb

A good source for small O rings, especially the really tiny ones, is your local watch repair shop. They do sell O-ring kits for watches online but you wind up buying a lot more than you might want.

1QwkSport2.5r

I'll keep this in mind, Earl. My rc car engines' carburetors have some really tiny o-rings that I've had trouble finding more recently. I ended up buying 3-4 o-ring kits for various engines to get the sizes I needed.

I dont even know of any watch repair shops in my area now that I think of it. I'll have to look around.

copelab

Sent another p.m. Jim
Bob

copelab

Success and failure(sort of). Replaced idle disc o-rings and managed 6 flights with no dead sticks. However,this morning the engine threw the prop in the air and I lost the prop nut,washer and prop driver. I have just fired off an order to MECOA for some parts.Thanks to 1qwksport2.5r and srqflyer(new o-rings) for their help.
Bob

1QwkSport2.5r

Glad you got the issue sorted out.

copelab

A couple of successful flights today. I burned out my plug by accident,replaced it with a Fox long reach with an idle bar.an it ran fine. Almost time to pack it in for the winter.
Bob

Lou Crane

Just a thought... I've just wandered through the whole thing and it is an excellent experience!

However, as with the FOX forum, reading forward from Post #0 is discouraging at best, frustrating otherwise. (Our sites are not "Genesis" -"...In the beginning was the Word...)

SYSOP. Moderator, or whatever title of service you prefer, would it be possible, perhaps preferred by visitors?, to offer posts in inverse date order? - from today back? I value your service and efforts very highly - just want to offer my thought that we might have more hits - and regulars - and good added comment - if we 'read the posts from today back.'

Whatever... pleeze keep it going (or would that be "coming?" ) GREAT valuable discussions and info either way!

1QwkSport2.5r

I was lucky enough to procure a brand new in the box Sportster .45. Older non-bushed crankshaft and needle valve on the carb. She's pretty tight, so a typical Sportster break-in will be in order. I need to find a Diesel head for it. If anyone has any leads on one, let me know.

AmishWarlord

My Feedback: (5)

I'll keep an eye out Quick.

Lou, I thought about that but the first few post have a ton of into on the engines and places to get upgrades. I want new people to see the info post first.
You can allways click the "SEE LAST POST" tab.

1QwkSport2.5r

Thanks AW. I now have one each of the .20, .28, and .45 and 2X .65s. The .20 is a diesel conversion now. The .20 turns a 10x6 at 10,020rpm and 11x6 at 8,790rpm. Compared to an Irvine .20 diesel runs about 8,200rpm (average) on a 10x6.

1QwkSport2.5r

I dug out my Sportster collection. The .20 is the only one with the O-ringed head which makes it an early model; and no bronze bushing on the crank. This .28 has the bronze bushing on the crank and is the only one of the 5 that does. The .45 and both .65s are earlier models - not having the bronze bushed crank. So far only the .20 and one .65 have been run. The other three are unrun.

dennis

My Feedback: (90)

the Sportsters all use a 1/4-28 nut, so do a lot of the other guys engines. I've even found what I need at Ace hardware or True value stores. You can also over pay and get them from Tower or any other hobby supplier as they are also used on OS, Thunder Tigre you get the idea. The all sell the appropriate washers too

Dennis

1QwkSport2.5r

If one prefers to use spinner nuts, they can be obtained online or from your hobby shop for around $10. I prefer spinner nuts to spinners as they are a "one and done" deal and don't require balancing like regular spinners do. A regular old nut works well also, but for the guys that like to use electric fingers, they may not work as well without the appropriate starter cone.

I do not like using electric fingers on my Sportster engines though - it's hard on the engine having a bushed crankshaft.

sarpet

Can everyone tell rpm numbers?
K&b .65 sporster engine
10%nitro
Master 12x8 3blade prop.
Ithink replace saito.82 four stroke with k&b .65 sporster engine,that saito is worst engine ever.
Deciding to buy new motor from mecoa or proper old real k&b from ebay?

buzzard bait

Have you gone on any Saito threads to get help with your 82? So many people love those engines, plus it should be more powerful and lighter than a K&B 65. I would do everything possible to fix what is wrong with it rather than give up on it and get different engine. The 65 will require a LONG break in with high castor or all castor lube, and you'll always have to have a high castor fuel. The mufflers have two joints to leak from, and they will leak unless you seal them. You could wind up frustrated with that engine too. Get that Saito fixed, even if you have to send it somewhere!

1QwkSport2.5r

I think my .65 target drone engine turns a 13x6 APC in the mid 10k range on 5% nitro. I'd think a 12x8 3-blade would be around 10k or a little better maybe. Neither of my .65s had any pinch at TDC like my smaller Sportsters do, so they might be down on power a little from a standard "civilian" engine. I'd opt for the sportster, but only because I don't like Saito.