Well pure welcome and step up to the plate it sounds as thought you decided to join the big bore club well now that youve made that decision it get easier from there .

Now that you've made the decision to go big bore there is only the task of picking which co but that is easy there are only curently 2 co's. too choose from(THATS RIGHT I SAID 2)

1. PAMI snooty arrogant germans !!!! way expensive

2. TVI Crotchty old fart abit expensive

Well there you go you decide. I love my pami's and Gary at tvi has alway's treated me with frist class service.If you want top quality you must pay for it !!! if you want crap call me up i dish that out for free!! [img]i/expressions/face-icon-small-happy.gif[/img][img]i/expressions/face-icon-small-wink.gif[/img]

GOOD LUCK [img]i/expressions/face-icon-small-cool.gif[/img]

 

 

i have the tvi 720 what do you want to know? great power over stock but it takes a lot of the other stuff, carbs cams. the nice thing is you can go 760 at a later date. it will make banshees hate you, is that enough of what you want to hear? it might run with the 760's on the flats but the hill goes to the 760's but that will cost you another 3000, so how bad do you want to win?

 

hey man look at www.rpmsbigbore.com rick peterson is the best when it comes to dirtbikes. but he can or probally knows someone that can hook you up with 4wheeler motors. he can make a 125 two stroke have more power then a 250 2stroke with all the aftermarket stuff you can buy. maybe he can help.

 

I have a 102mm bore with an 11:1 piston (about a 680cc).

From what I have seen out there I think this is one of the most reliable for the bores but, of course the lowest gain in power of the bores (it is afterall the smallest bore!)

I have heard too many stories about leaking head gaskets on the 720/733's to believe investing in one is a wise move (TVI may have fixed this but, I think Sam Coe has had too many issues - albeit some may be old issues that are corrected on current builds.)

I don't want to sugar coat it so I'll tell you what I think - Spend the money and get Pami or don't go with the big bore and get a Ron Wood kit!

I may be going bigger (love to climb the steep dunes!) (Yes, there may be a 102mm bore cylinder & piston available - with a Nik coating!)

I agree with what has been already said about what you want the speed for. What are you doing? You can go bigger bore and get more overall power or you can go bigger compression and get more power. You can also go with a big set of cams and have a great hill shooter but, you won't have as good of a trail bike (2-stroke like power!)

The Pami 703 is a 102mm bore with a stroke to it as well. The Pami 760 is a 105.5mm bore (I think) on a new casting cylinder (so no sleeve) and a stroke too.

I don't believe the sleeves are the best way to bore these engines. (IMO)

The 720 is a 105mm bore with a sleeved cylinder (correct me if I am wrong.) The 733 is a 102mm bore with a 5mm stroke (again correct me if I am wrong), I don't know if the 733 has a sleeve or if it is a bore of the stock cylinder and a re-nik coating. There aren't many 733's out there.

There are three piece gaskets for the 102mm bore (680 and 703) as well as the 760 engine. These gaskets are better than the original metal gaskets that sealant was applied to to make up a gasket. (Has anyone re-used one of these gaskets?)

A 680 bore, re-nik and Piston will run you about $1200 (guess). You may be able to find a used one for about $700 [img]i/expressions/face-icon-small-wink.gif[/img]
You will want new cams and valve springs too (no matter which kit you go with!) Most people will suggest shim under bucket design. If you have larger valves put in at the same time you are looking at about $1,900 (Ron Wood pricing.)
The 703 kit (see Team Pami site for what it includes - more than just the bore/stroke) is about $3k (Euro) after freight taxes and exchange rate you are at about $3,900 USD.
The 760 kit is about $5 Euro add everything to it and you are probably near about $6,500.

If you do stroke you engine, you will either have a lot of labor to do yourself or you will be paying someone to do a lot of labor. I don't know if you can bore more than 102mm without work to the cases.

So, what are you looking for? (Don't tell me you want more information!) [img]i/expressions/face-icon-small-wink.gif[/img]

 

Im sorry Duneme, could you repeat that, I wasnt listening? lol[img]i/expressions/face-icon-small-smile.gif[/img]

So, your saying, that anyone could get a 680cc motor, by just regrinding and replating the cylinder to a 102mm bore. I guess Im asking if its safe to remove 2mm from the stock sleeve, and how much would be safe at a maximum? Did you notice any major differences for the extra 27 cc's? Our set up is identical other than the larger valves, which will come this winter, and Ive been reading about the bigger bore machines, but am not convinced they are safe yet. The 102mm bore sounds to be the safest, although the smallest. I am a machinest, and have access to all the equiptment needed to do this. Do you have to resize the combustion chamber of the head for just 2 millimeters? Thanks again for the info. Hopefully I did not ask a question that was already answered in your post, I see you spent alot of time typing.

Thanks,

Dstroyer,

P.S. DO ANY OF YOU PEOPLE HAVE JOBS???lol [img]i/expressions/face-icon-small-wink.gif[/img]

 

You say the "J" word once more and we will have you floged!! there will be none of that working crap around here!![img]i/expressions/face-icon-small-blush.gif[/img][img]i/expressions/face-icon-small-smile.gif[/img]

And yes duneme you better get a copyright on that baby!!

And a samcoe 733 is all bore and stroke no sleeve here [img]i/expressions/face-icon-small-shocked.gif[/img]

 

man those things cost a lot of money[img]i/expressions/face-icon-small-smile.gif[/img] it all comes down to if you can get the head to seal up. seems that i've never heard of a problem with the 102 bore and reseal. but how high of compression are they running on those?seems anything that isn't stock can cause a few problem. seems that some have less than others, azsand might have a word or two to add here.

 

OH i think the samecoe bore seals just fine in my opion. I think it held good compression right up until the piston smacked it so hard it ripped out a stay bolt. Which was right after the rod peeled open my cases like a grapefriut at breakfast. And that was right after the rod came threw the front of the motor so hard it pirerced my starter slaming it threw my headers and radiator(also putting a nice dent in my frame!! YES i would say the samcoe head was sealing exellent up until that point[img]i/expressions/face-icon-small-happy.gif[/img]

 

AZsand,

So are you trying to say that the samcoe kit didnt work for you!!! lol Im not clear on where the problem was. lol Did you get any shrapnel in the legs? Holy crap man, I would be one pissed of SOB if that happened to me. Its good to see your not holding any grudges. lol[img]i/expressions/face-icon-small-happy.gif[/img] In the imortal words of Bill Clinton, "I feel your pain"

DStroyer