85 R after carb tune

[barnett468]

Hello

It's not a crank seal, checked it out as my 03 RM 250 had bog issues, thought it was a case seal and replaced. Ended up being too big a jet and running klotz R50.

Unfortunately this is a different bike and if you re-read my previous post again you will see why I don’t think it is caused by an over rich condition but it is still possible.

Thanks for that leak test video, Went out ridding today on my RM and before I left I changed the oil on my 250r. When I pulled myself off the ground using the kicker i heard a "FFFFFFFFT" I look over and its blowing out of where the anti-freeze leaks. You can deff see and hear it just by cranking it over with your hand. Seems to me like a gasket. Im going to take the motor out this week and open her up. I'll take pictures tomorrow.

Please don’t convolute the issue by talking about a different bike, it can be confusing. Which bike has a leak?

If your Honda has a leak it can be from a warped cylinder and/or head, aftermarket head gasket, improperly torqued head.
You can check flatness by placing a piece of black 400 grit sandpaper on a granite countertop, color head and cylinder sealing surfaces with a felt pen [after cleaning] then put some water on paper rotate both on paper using moderate pressure for 3 turns then see if any black felt marks are left. If there are continue sanding until marks are 100% gone.

REPLACEMENT GASKET – If your bike was NOT detonating/pinging I would replace gskt with exactly the same as what is currently in there. You can determine what you have by measuring it, see list below. It will be a few thousands smaller than one of the two on the list since it has been compressed slightly. So if it’s thicker than the orig gskt it is a TRX gskt.


3 piece OEM gskt for TRX 250R is .060" for the orig and probably also the updated 1 piece gskt.

1 piece OEM fiber gskt for ATC 250R 85-86 and CR 250R 86-89 is .040". I don’t know if this measurement is for the orig gskt or updated gskt thickness but they are probably both the same


If it’s an ATC/CR 250r gskt then buy the new updated p/n 12254- KS7- 881 or 12254KS7881 it probably seals better than the orig.

OEM FICHE 85-86 ATC 250R AND PARTS SUPPLIER, HEAD GASKET AVAILABLE, ITEM 4.
http://www.cmsnl.com/honda-atc250r-1...1.html#results


If it’s a TRX 250R gskt for some reason then I would replace it with an orig updated TRX one p/n 12254-HB9-013 from site above.

I would not use any sealer, others would.

I use 32:1 klotz 20/80 super techniplate. SMELLS GREAT!

The ratio is good however it is possible this stuff is causing at least some of the black color on your plug.

I'll try a new plug after I open her up.

I’m “guessing” by your comment that this IS the same plug that was in it BEFORE you installed the latest carb. This means that this plug can not be used to help determine ANYTHING regarding your latest potential carb and jetting or oil burning problem.

I did not touch the jets when i got the carb, Ill do the drill test, and match some jetts up.

Ok good.

Also, the trike can idle all day and not load up. Runs real crisp. Something the last carb could not do.

Again this suggests your max rpm miss is not caused by an overly rich condition.




What EXACT gas brand, type and octane are you using?

[JasonB]

I am actually installing the 38mm carb off my cr500 onto a buddies 85 bike. We were at the St Joe ride and his bike was running bad so I started messing with the carb and first thing I found was the round slide carb top was stripped and becoming a big air leak. anyways, i am putting the stock cr500 carb on a buddies stock 85 250r hopefully next weekend, I put a 160 main and 50 pilot in there and will jet up/down as needed. he will probably be in the same boat as you lol


sounds like you are starting to get things narrowed down, its all in chasing the small stuff to make it run perfect!

[JasonB]

It's not a crank seal, checked it out as my 03 RM 250 had bog issues, thought it was a case seal and replaced. Ended up being too big a jet and running klotz R50.

Thanks for that leak test video, Went out ridding today on my RM and before I left I changed the oil on my 250r. When I pulled myself off the ground using the kicker i heard a "FFFFFFFFT" I look over and its blowing out of where the anti-freeze leaks. You can deff see and hear it just by cranking it over with your hand. Seems to me like a gasket. Im going to take the motor out this week and open her up. I'll take pictures tomorrow.

I use 32:1 klotz 20/80 super techniplate. SMELLS GREAT!

I'll try a new plug after I open her up. I did not touch the jets when i got the carb, Ill do the drill test, and match some jetts up. Also, the trike can idle all day and not load up. Runs real crisp. Something the last carb could not do.

Thanks for the help! I'll keep the thread updated with progress and pictures.

dont know if i missed it, but is it leaking at the top of the cylinder (head gasket) or the bottom of the cylinder (base gasket)? if its blowing out with you just rolling the kicker than you shouldnt ride it again until you replace the corresponding gasket lol Also, I LOVE techniplate! I run a 40:1 in my 310 and mix with 110 race gas. Smells like perfume together and dont know if I missed it too but the plug gap that billy suggested is a big deal. throw a br8es or br9es in there gapped .18-.20 and see how she does after you swap that gasket out. Barnett suggested a perfect way to ensure the cylinder head is smooth flat. Had to do that with my 84 air fooler that kept burning copper gaskets and warping the head

[Billy Golightly]

Also, and this may be a dumb question, but how heavily oiled/ dirty is your airfilter?

[RIDE-RED 250r]

By the fact that you are eluding to a coolant leak, that pretty much indicates a blown head gasket. The cylinder base gasket does not seal any coolant jackets as there are none present that far down in the cylinder. What you see that kind of looks like coolant jackets at the base of the cylinder is the transfer ports castings...

Pull the head and check for warpage as Barnett suggested. If OK, clean clean clean both the head and cylinder mating surfaces, check closely for cracks, and replace the gasket. Make sure to torque head nuts to proper torque and in a criss-crossing pattern. Sometimes it's a good idea to torque all the nuts to half of the listed torque spec then torque them up to full listed torque spec. This is a good way to make sure you don't torque unevenly when installing the head.

Do the head gasket before riding more. And if the problem still persists let us know.....

Oh and if the problem leads to checking the CDI, the OEM CDI will have a little sticker on the side of the plug with "HA-2" or "HA-5".. I can't remember which number it exactly is, but the "HA" part I remember 100%. I have not seen an aftermarket CDI labeled as such. "HA" is a standard component of Honda's part numbering system..... Also the OEM CDI will be black... Many aftermarket units are orange or red...

[just ben]

according to your pic with the red circle indicating the coolant leak,that would be the base gasket. I really can't see it leaking out coolant there even if the waterjacket were cracked at the bottom.(on the inside) My guess would be its leaking up higher and is pooling up there leading you to thing it is leaking there.If it is leaking air there it would be easy to tell by spraying carb cleaner in that area while it's running.