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Cylinder Boring


RigPig

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Hi Guys

I am about to start (another) major upgrade to the Harley. It has an 88 Cu Inch motor and I want to take it up to 95 Cu Inch, they have enough "meat" to go to 98 Inch so that's not an issue and i can get a good set of high compression pistons out of the States at a fair price. However machining in Thailand scares me. But I wouldn't think that boring out a set of barrels would be that big a deal. Does anyone know of a reputable and reliable machine shop where I could get this done? I live in Phuket but don't mind if I have to travel or have them sent somewhere as long as the job is done right.

Thanks in advance

Tony

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I'm doing the same, from 96 to 107. I just bought a set of cylinders and heads from someone on one of the forums in the States.Going to have them done over there, pistons will have the rings gapped too. Bore and wiseco pistons and stage II heads ported.

If you don't want to do that then you could just buy new ones ,S&S are selling cylinders and pistons on ebay for about $630.

Shipping is the big problem DO NOT HAVE THEM SHIPPED BY ANY COURIER COMPANY PLEASE Use USPS, probably the best way.

Have you thought about cams, or did you do them already?

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I'm doing the same, from 96 to 107. I just bought a set of cylinders and heads from someone on one of the forums in the States.Going to have them done over there, pistons will have the rings gapped too. Bore and wiseco pistons and stage II heads ported.

If you don't want to do that then you could just buy new ones ,S&S are selling cylinders and pistons on ebay for about $630.

Shipping is the big problem DO NOT HAVE THEM SHIPPED BY ANY COURIER COMPANY PLEASE Use USPS, probably the best way.

Have you thought about cams, or did you do them already?

FB, going to 107ci, do you have to oversize the sleeve bores in your block or still plenty of room? Just curious :)

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Just a tip. A lot of Thai machine shops machine the bores to match the pistons, so they will probably need the pistons as well as the barrels. It is just the way they do it.

That is the only way in my opinion. With all my performance engines, the pistons are matched to the bored cylinder and marked accordingly for assembly. The other way is to buy matched barrels & pistons, which would be an easier, presumably less painfully route in Thailand.

Sent from my SM-T211 using Tapatalk 4

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Just a tip. A lot of Thai machine shops machine the bores to match the pistons, so they will probably need the pistons as well as the barrels. It is just the way they do it.

That is the only way in my opinion. With all my performance engines, the pistons are matched to the bored cylinder and marked accordingly for assembly. The other way is to buy matched barrels & pistons, which would be an easier, presumably less painfully route in Thailand.

Sent from my SM-T211 using Tapatalk 4

I concure, that isn't a problem. I would walk away if they intended to do it without the pistons !! I can get a complete set of 10:1 Wiseco pistons, rings and gudgeon pin for around $340 out of the States and shipping on those (and tax etc.) wouldn't be too painful. Shipping barrels just for the sake of having them bored seems extreme, except for the fact we are in Thailand....

I still haven't had any suggestions of where to go. Are there any big engine reconditioning companies in Thailand? We had companies like REPCO in Aus and others. As I said earlier it would be nice if I could find somewhere in Phuket but I am prepared to travel if necessary. I could have everything I need waiting to go and get the job done in one hit if I could find somewhere to get the barrels bored. Is there anywhere to get the heads ported in Thailand that wouldn't mess it up? Maybe there is an opening here for a business opportunity......

Thanks for the help everyone

Oh and Garry It is my understanding that you can go from 96" to 103" no problem it's the same as going from 88" to 95" This leaves "plenty of meat" still on the bores. The max on 88" is 98" but that means you have almost nothing left. To go from 96" to 107" I think you will have to swap the crank shaft (basically it is a stroker) which is the difference between the 88" and 96", the bores are actually the same, the 96" has a longer stroke which is where it gets the bigger capacity from. I hope that helps.

Also FY theI pre 2007 motor cams had a link chain set up with spring loaded tensioners and post 2007 have a roller chain and hydraulic tensioners. HD changed this out for a reason. I am upgrading mine from link to roller and will be swapping out the cam at the same time probably an Andrews 37. You can also go geared but it has some issues attached too.

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Get them to gap the rings and match/mark as Garry said.

And as you're importing, consider getting a spare set of rings. It's hugely embarrassing if you break a ring during assembly or gapping. Or since this is Thailand, comes back from the machine shop sans one or more rings.

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Contact Hot Rod Harley Davidson in Pattaya.

Gary is the Englishman who deals with the customers, as the owner Ed is so busy.

HD and only HD. Done lots - he knows where to send them.

Thanks Seedy, it looks like they have a web site (http://www.hotrodpattaya.com) but no email address, I am in the middle of the dessert in Saudi Arabia at the moment. I'll have to try to call them from Skype as we have Internet (but via satellite) but it's pretty average.

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Get them to gap the rings and match/mark as Garry said.

And as you're importing, consider getting a spare set of rings. It's hugely embarrassing if you break a ring during assembly or gapping. Or since this is Thailand, comes back from the machine shop sans one or more rings.

Good thinking Gsxrnz thumbsup.gif

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I concure, that isn't a problem. I would walk away if they intended to do it without the pistons !! I can get a complete set of 10:1 Wiseco pistons, rings and gudgeon pin for around $340 out of the States and shipping on those (and tax etc.) wouldn't be too painful.

you will pay 30% import tax + 7% vat.

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There's a little repair shop on Sukhumvit Rd Jomtien East I have used for machining jobs.....but I haven't had a rebore done. The guy does a lot of repairs on outboard motor parts, TIG welding, machining. If he doesn't do rebores on Harley barrels I'll bet London to a brick he knows who can.

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I concure, that isn't a problem. I would walk away if they intended to do it without the pistons !! I can get a complete set of 10:1 Wiseco pistons, rings and gudgeon pin for around $340 out of the States and shipping on those (and tax etc.) wouldn't be too painful.

you will pay 30% import tax + 7% vat.

My experience is that there is no consistancy, if it's big and shiny and addressed to a Farang you are gonna pay !!! And yet some things coe through with no tax at all (doesn't balance out though). I imported an entire 6 speed gearbox and got right royally raped, it was miles over the 30% +7%. I asked my accountant to dispute it the reply she got was "No problem but you will be paying 3000 Baht a day storage fees while we look into it"

TIT

Still cheaper than buying quality forged high compression pistons here I think, and I should get the real thing....

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I concure, that isn't a problem. I would walk away if they intended to do it without the pistons !! I can get a complete set of 10:1 Wiseco pistons, rings and gudgeon pin for around $340 out of the States and shipping on those (and tax etc.) wouldn't be too painful.

you will pay 30% import tax + 7% vat.

All depending on the mood of the post master. My last two orders I have only been charged VAT. :)

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Just a tip. A lot of Thai machine shops machine the bores to match the pistons, so they will probably need the pistons as well as the barrels. It is just the way they do it.

That is the only way in my opinion. With all my performance engines, the pistons are matched to the bored cylinder and marked accordingly for assembly. The other way is to buy matched barrels & pistons, which would be an easier, presumably less painfully route in Thailand.

Sent from my SM-T211 using Tapatalk 4

I concure, that isn't a problem. I would walk away if they intended to do it without the pistons !! I can get a complete set of 10:1 Wiseco pistons, rings and gudgeon pin for around $340 out of the States and shipping on those (and tax etc.) wouldn't be too painful. Shipping barrels just for the sake of having them bored seems extreme, except for the fact we are in Thailand....

I still haven't had any suggestions of where to go. Are there any big engine reconditioning companies in Thailand? We had companies like REPCO in Aus and others. As I said earlier it would be nice if I could find somewhere in Phuket but I am prepared to travel if necessary. I could have everything I need waiting to go and get the job done in one hit if I could find somewhere to get the barrels bored. Is there anywhere to get the heads ported in Thailand that wouldn't mess it up? Maybe there is an opening here for a business opportunity......

Thanks for the help everyone

Oh and Garry It is my understanding that you can go from 96" to 103" no problem it's the same as going from 88" to 95" This leaves "plenty of meat" still on the bores. The max on 88" is 98" but that means you have almost nothing left. To go from 96" to 107" I think you will have to swap the crank shaft (basically it is a stroker) which is the difference between the 88" and 96", the bores are actually the same, the 96" has a longer stroke which is where it gets the bigger capacity from. I hope that helps.

Also FY theI pre 2007 motor cams had a link chain set up with spring loaded tensioners and post 2007 have a roller chain and hydraulic tensioners. HD changed this out for a reason. I am upgrading mine from link to roller and will be swapping out the cam at the same time probably an Andrews 37. You can also go geared but it has some issues attached too.

Thanks for the reply PR, Ah okay, that's clear enough and a stroker crank makes sense then. I suppose it's not too big a jump and you wouldn't probably need to mill the upper crank case for conrod clearance at all. Keep us posted on how things develop. Cheers :)

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Just a tip. A lot of Thai machine shops machine the bores to match the pistons, so they will probably need the pistons as well as the barrels. It is just the way they do it.

That is the only way in my opinion. With all my performance engines, the pistons are matched to the bored cylinder and marked accordingly for assembly. The other way is to buy matched barrels & pistons, which would be an easier, presumably less painfully route in Thailand.

Sent from my SM-T211 using Tapatalk 4

Blimey are Harley pistons made so inarticulately that each requires a different bore size? I have never heard of that, in most countries they sell you stock pistons after you have had the rebore, purely based on the bore measurement. It does explain why they have vibration problems, but what an odd way to ensure it, cutting two different bores and fitting two different sized pistons..

I would concur that you should give them the pistons here in Thailand. I have had two rebores done here and both were okay, it aint rocket science, even for Thais, who do it a lot.

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Just a tip. A lot of Thai machine shops machine the bores to match the pistons, so they will probably need the pistons as well as the barrels. It is just the way they do it.

That is the only way in my opinion. With all my performance engines, the pistons are matched to the bored cylinder and marked accordingly for assembly. The other way is to buy matched barrels & pistons, which would be an easier, presumably less painfully route in Thailand.

Sent from my SM-T211 using Tapatalk 4

Blimey are Harley pistons made so inarticulately that each requires a different bore size? I have never heard of that, in most countries they sell you stock pistons after you have had the rebore, purely based on the bore measurement. It does explain why they have vibration problems, but what an odd way to ensure it, cutting two different bores and fitting two different sized pistons..

I would concur that you should give them the pistons here in Thailand. I have had two rebores done here and both were okay, it aint rocket science, even for Thais, who do it a lot.

Where did you get the rebores done? I agree it shouldn't be rocket science, the idea of supplying the pistons and rings is so after the rebore the rings can be "gapped" correctly to suit each cylinder individulally. The pistons I am using are Forged Wiseco 9.5:1. If the Thai (presumably but anyone really I guess) doing the job has the pistons so hopefully will get the bore size right by measuring it. I think that's the reasoning behind it.

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Just a tip. A lot of Thai machine shops machine the bores to match the pistons, so they will probably need the pistons as well as the barrels. It is just the way they do it.

That is the only way in my opinion. With all my performance engines, the pistons are matched to the bored cylinder and marked accordingly for assembly. The other way is to buy matched barrels & pistons, which would be an easier, presumably less painfully route in Thailand.

Sent from my SM-T211 using Tapatalk 4

Blimey are Harley pistons made so inarticulately that each requires a different bore size? I have never heard of that, in most countries they sell you stock pistons after you have had the rebore, purely based on the bore measurement. It does explain why they have vibration problems, but what an odd way to ensure it, cutting two different bores and fitting two different sized pistons..

I would concur that you should give them the pistons here in Thailand. I have had two rebores done here and both were okay, it aint rocket science, even for Thais, who do it a lot.

To be accurate you should always bore the cylinder to suit the piston.

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Just a tip. A lot of Thai machine shops machine the bores to match the pistons, so they will probably need the pistons as well as the barrels. It is just the way they do it.

That is the only way in my opinion. With all my performance engines, the pistons are matched to the bored cylinder and marked accordingly for assembly. The other way is to buy matched barrels & pistons, which would be an easier, presumably less painfully route in Thailand.

Sent from my SM-T211 using Tapatalk 4

Blimey are Harley pistons made so inarticulately that each requires a different bore size? I have never heard of that, in most countries they sell you stock pistons after you have had the rebore, purely based on the bore measurement. It does explain why they have vibration problems, but what an odd way to ensure it, cutting two different bores and fitting two different sized pistons..

I would concur that you should give them the pistons here in Thailand. I have had two rebores done here and both were okay, it aint rocket science, even for Thais, who do it a lot.

Where did you get the rebores done? I agree it shouldn't be rocket science, the idea of supplying the pistons and rings is so after the rebore the rings can be "gapped" correctly to suit each cylinder individulally. The pistons I am using are Forged Wiseco 9.5:1. If the Thai (presumably but anyone really I guess) doing the job has the pistons so hopefully will get the bore size right by measuring it. I think that's the reasoning behind it.

The pistons are useful for 4 reasons:-

1. To ensure nothing is lost in the translation. Inches instead of millimetres, TIT.

2. Check for diameter by fitting.

3. Check for taper..

4. Check for concentricity.

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I have done this many times and while not rocket science is needs to be done right and carefully.

Yes you need the pistons at the machine shop and run away if he is willing to do it without the pistons in hand. Machine each cylinder individually to fit that specific piston

USE TORQUE PLATES when boring the cylinders. This is critical to getting a proper job and nice round bores. I suspect that very few shops in Thailand do this but I do know that Richco in Chiangmai has a set of plates that he installs and then takes the complete set up to the machine shop for boring.

The machine shop is the big one just off the moat on the way to Surawong bookstore, if you want to go it alone without torque plates

Go slowly with lots of coolant. Let the cylinder cool down on the last couple of passes and between each pass. Pay them extra for the machine time if they insist, but doing the main cuts before lunch and the finish cut(s) after lunch is a good way to allow cool down

Check that both faces of the cylinder are true and parallel after boring.

I have gone as far as to machine a collar to support the spigot portion of the cylinder so that it does not distort when bored. Not really necessary on a street engine, but gives me peace of mind when things get hot

Honing is an art in itself however you will have little choice here. Gap them yourself to know that it is correct and seat them right in the first 50Km and you will be fine with the Weisco pistons

If you are buying cams and thinking of the hydraulic tensioner upgrade, forget it and buy a gear drive. A bit noisy but trouble free, and the gear whine cannot be heard over the pipe anyway

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