Traded my DG head for a 300 kit!!

[Jheezy7]

So after tracking down a 300 kit on craigslist, I talked the guy into partin with it! :Bounce:Bounce:Bounce and it's a good thing I had some extra parts lying around because he didn't want money..I traded a DG head, some paddle tires(and a few other miscellaneous parts off my 250r)..I loved the gold head but it was for an 81-82 and I didn't want to hack it up to make it fit on my bike(83')..I don't know what all came with a 300 kit but I got the head and cylinder..Now I just need to find a piston for it and have it put on..I also have a new exhaust I'll be putting on at the same time and I already have a new uni filter, pj34 carb, rad valve and spacer already on(just to give you guys an idea of what else I'll be running with it)..

Now I think I read somewhere that Wiseco or another company will make a piston to fit any head?? :wondering I realize that I could just measure the inside of the cylinder and buy a piston off ebay that's the same size(I think?), but what I want to do is send my motor away or take it to the pros to have the head put on and possibly ported with a piston made for it that's the right size. A rough measurement of the inside of the cylinder it looks to be close to 76mm(give or take 1 mm)...Does anybody know of any such place where I can either get a piston made or send my motor to be put together?And if so, how much does it cost to do this? And if there's any other tips/info for someone putting together a 300 motor I'm open..I've seen some pretty sweet 300r's on this website..I posted some pictures to show off my junk..lemme know what you think..thanks!

[6speedthumper]

I looked into getting pistons made for a hotrods stroker crank for my Warrior, and both JE and Wiseco need a minimum order of 4 pistons at nearly $250 a shot. Best bet is to keep talking to guys here that have gone this route.

[bigdaddyvw185]

once and a while OEM 300 parts pop up on ebay but that does not happen all that often. I have seen more 300 kit piston rings come up on ebay more often than the pistons. if you want to start searching ebay for OEM pistons do the searches by the part number of the piston size you are looking for, All the part numbers for the pistons from the 300 kit end in 810. the 300 cylinder that originally came with my trike was blown and needed a 76.75 piston set, and after almost a year of looking i have only been able to get my hands on a ring set, No luck on the 76.75 piston. I was able to find a nos cylinder, rings, and piston from a member on the pilotodyssey forums and ended up going with that, tho before i came across that i was very close to going with the racerstoystore mod with my original cylinder.

[Jheezy7]

Thanks for the info guys..if I find a piston with the part number ending in 810 how do I know what size it is? I found one on ebay but it doesnt say anything about its size..

http://www.ebay.com/itm/NOS-Honda-1983-1984-ATC250R-Piston-Standard-OEM-13101-964-810-/190864159003?pt=Motorcycles_Parts_Accessories&hash=item2c7063f11b&vxp=mtr

[sledcrazyinCT]

Says in the sellers ad that it is standard size. look at the last # in the first group of numbers 1 is STD 2 is .25 3 is .50 oversize and so on

[Jheezy7]

Found an ended listing for a big bore piston kit...would this work?? pretty sure the seller still has it..and how much would it cost to go the 330 route?

http://www.ebay.com/itm/81-84-ATC250R-PISTON-KIT-BIG-BORE-6mm-76mm-/271355124994?vxp=mtr

I appreciate the insight guys..most of this stuff is wayy over my head..

[bigdaddyvw185]

Here are the part numbers for the pistons / rings for the 300 kit, from standard 76mm threw the overbore's to 77mm

13101-964-810 ------ Standard 76mm piston
13102-964-810 ------ 1st overbore piston 76.25
13103-964-810 ------ 2nd overbore piston 76.50
13104-964-810 ------ 3rd overbore piston 76.75
13105-964-810 ------ 4th and final overbore piston 77.00

130A1-964-810 ----- Standard ring set 76.00
130A2-964-810 ----- 1st overbore ring set 76.25
130A3-964-810 ----- 2nd overbore ring set 76.50
130A4-964-810 ------ 3rd overbore ring set 76.75
13105-964-810 ------ 4th and final overbore ring set 77.00

12254-964-810 ------ 300 kit cylinder head gasket
Here is a link for a headgasket that is on ebay right now, at an awesome price by the way!
http://www.ebay.com/itm/Genuine-Honda-Motorcycle-Dirt-Bike-Cylinder-Head-Gasket-12254-964-810-New-/281249981163?pt=Motorcycles_Parts_Accessories&hash=item417bce22eb&vxp=mtr

[Daddio]

Found an ended listing for a big bore piston kit...would this work?? pretty sure the seller still has it..and how much would it cost to go the 330 route?

http://www.ebay.com/itm/81-84-ATC250R-PISTON-KIT-BIG-BORE-6mm-76mm-/271355124994?vxp=mtr

I appreciate the insight guys..most of this stuff is wayy over my head..

No, that wouldn't work. This is for the stock cylinder. My son has one in one of his 250R's.

[3 Wheel Drive]

I had no idea the 300 kits were like that, I picked up an 81 with a 300 kit. So far I have not spent much time with it. Is it really that difficult to find the pistons and rings?

It seems like I see 250rs with 300 kits quite often in my area. Just out of curiosity, what does a complete 300 kit go for?

[sledcrazyinCT]

12254-964-810 ------ 300 kit cylinder head gasket
Here is a link for a headgasket that is on ebay right now, at an awesome price by the way!
http://www.ebay.com/itm/Genuine-Honda-Motorcycle-Dirt-Bike-Cylinder-Head-Gasket-12254-964-810-New-/281249981163?pt=Motorcycles_Parts_Accessories&hash=item417bce22eb&vxp=mtr (http://rover.ebay.com/rover/1/711-53200-19255-0/1?campid=5336526073&toolid=10001&mpre=http://www.ebay.com/itm/Genuine-Honda-Motorcycle-Dirt-Bike-Cylinder-Head-Gasket-12254-964-810-New-/281249981163?pt=Motorcycles_Parts_Accessories&hash=item417bce22eb&vxp=mtr)

Thanks Chris I snagged this today!

[bigdaddyvw185]

I thought about grabbing it the second i saw it and having it as a spare but I am glad you snagged it Jim, How is the search going for a .25 piston? any luck?

[90guy]

Thanks Chris I snagged this today!
Dang it! I just got on and saw this. lol I was going to grab it for my 300r.

[Jheezy7]

Thanks bigdaddyvw185 for those part numbers/link..I've been watching your build brotha it's lookin sick! Engine looks really good, can't wait to see that bad boy up and runnin!..and thanks sledcrazyinCT for snaggin up that head gasket for me, lemme send you my address..:lol:..I laugh now but something tells me I'll be looking for another one of those for the next six months...So my next question(s) is this..
1) If my cylinder is at a stock 76mm right now(which I think it is), and there's a 76mm 300 piston on ebay right now(and rings), why would I need to go at least first overbore?? The inside of the cylinder looks like it is in pretty good shape..
2) How do I measure the inside of my cylinder to find out what size piston I need?
3) If one of my bolts is snapped that attaches the head to the cylinder, that's replaceable right?(it's sheared off even with the top of the head)
4) And Daddio, when you say that piston is for a stock cylinder, you mean the stock 300 cylinder right?(I'm pretty sure my cylinder IS the stock 300)
Thanks again guys..:beer

[Jheezy7]

Here's a pic of the sheared bolt..
185116

[bigdaddyvw185]

Thanks bigdaddyvw185 for those part numbers/link..I've been watching your build brotha it's lookin sick! Engine looks really good, can't wait to see that bad boy up and runnin!..and thanks sledcrazyinCT for snaggin up that head gasket for me, lemme send you my address..:lol:..I laugh now but something tells me I'll be looking for another one of those for the next six months...So my next question(s) is this..
1) If my cylinder is at a stock 76mm right now(which I think it is), and there's a 76mm 300 piston on ebay right now(and rings), why would I need to go at least first overbore?? The inside of the cylinder looks like it is in pretty good shape..
2) How do I measure the inside of my cylinder to find out what size piston I need?
3) If one of my bolts is snapped that attaches the head to the cylinder, that's replaceable right?(it's sheared off even with the top of the head)
4) And Daddio, when you say that piston is for a stock cylinder, you mean the stock 300 cylinder right?(I'm pretty sure my cylinder IS the stock 300)
Thanks again guys..:beer

To answer some of your questions
1. even if your cylinder is at the stock 76mm right now it would be a good idea to go up to the next overbore at 76.25. that way your starting with a fresh bore that you no is in good shape and not just going on a hunch. tho you NEED to figure out what bore your cylinder is currently at to even start shopping for a replacement piston, if your 100% sure your at 76.00mm now then go up to 76.25, if your at 76.50 now then go to 76.75, so on and so on.... Or ya could just get in touch with the guys over at racerstoystore and go the 330 mod route and just bypass all the standard piston searching.
2. to measure the bore, get yourself a dial caliper (metric or standard, with a standard just convert the measurement ya end up with to metric with a conversion calculator on the computer), then measure the bore in multiple different locations on the cylinder. then take the average.
3. Yes the head bolts are replaceable and are still available for the 250R cylinders (not 100% sure if they are the same for the 300 kit) the head bolts are item number 17 from this web site http://www.partzilla.com/parts/search/Honda/ATV/1984/ATC250R+A/CYLINDER+HEAD+%2B+CYLINDER/parts.html
4. When Daddio said that piston was for a stock cylinder he was referring to a stock 250 cylinder not the 300 cylinder

[snowhoundxp]

Bought a Honda Line 300 kit of A guy on Marks Vintage swap meet. This guy had a couple kits and I talked him into selling his second spare. I missed out on the first one So I asked him about a piston and he told me too search ebay ATC250r big bore kit. A sleeve came up and the store was cylinder-resleeve-replate-exchang. So I called and he said he had all sizes of piston and rings and he can bore your cylinder. I am pretty sure he told me $189 for piston and rings. I hope this helps.

[Jheezy7]

Thanks snowhound..I went on ebay and found that guy's store and he quoted me a price on a new sleeve, piston, rings, gaskets, and stud for $394.30..think I'm gonna go that route..however his gasket sets are $50..SledcrazyinCT u wanna sell me that gasket you bought off ebay for $10?..I'll give you $20 you'll double your money...and thanks bigdaddy for the info..I got your pm..I read that powerplay article when you posted it on your build thread..interesting stuff....I had the inside of my cylinder checked out and it was noo good..proly overheated and blew a gasket 20 years ago..any body have an extra gasket for the 300 kit they want to sell?

[sledcrazyinCT]

Keep an eye on this ebay seller his ad said this gasket was from a bulk package so maybe he has more of them to sell?

[Jheezy7]

I asked the seller if he had any other 300 kit gaskets..he said no..he said he wouldn't be getting any more either..he bought a box of gaskets at an auction and the 300 gasket was in the box..

[3 Wheel Drive]

I ran across this today, ad says they have 300 kits. May be worth someone's time to call them.
http://losangeles.craigslist.org/sfv/mcy/4264596642.html

[Jheezy7]

So..I sent my cylinder and head off to be bored and honed yesterday by Cylinder-Re-plate-Re-sleeve-Exchange(thank you snowhoundxp)..and before I did I thought I'd take the head off and package the head and cylinder separately so that I wouldn't damage any of the fins during shipping..up til this point I hadn't separated the two mainly because I didn't have any reason to..and sure enough lying there right on top of the cylinder was a 7 stud copper gasket..now naturally I figured when I received the head and cylinder that if the piston and rings are gone that there probably wasn't going to be any gaskets either and even if there was I would have to replace em..but I didn't realize it was a copper gasket..so my question is...can a copper gasket be re-used? 185894

[90guy]

Ive did some reading on this but have never did. I have heard to anneal the gasket. And then I have heard other people use the copper head gasket spray coat it and place it back on. I am just replacing the one on mine and keeping the old one if its still decent to have a spare.