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first top end Suggestions?

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I'm doing my first top end and I need some suggestions on what oil to use for break in. Is lucas simi synthetic racing oil you get at O'Reilly okay to use?

do you have any tips for me when doing my first top end?.

the bore jetting and pipe are stock but the silencer says bbr 4 stroke on it. any suggestions are appreciated thanks

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I just used premix...?

- Be careful when scraping the old gasket off your cylinder base and head, it's easy to score them

- Make sure you get the circlip installed all the way in

- Stuff clean shop towels around your rod in the bottom end while you work so you don't drop anything in there (like said circlip)

- Take care to check your work as you go (so you don't install the piston backwards, for instance)

It's not too hard really, just take your time and enjoy it. Good luck! :thumbsup:

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get scotch bright pads wd-40 the cylinder bore clean it with the pads in a circular motion to restore the cross hatch then use a paper towel with down on it and clean the bore the same way till the paper towels come out white it may take a few times to get it clean .. also set the ring gap

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what kind of oil should I use for break in some say the rings wont seat if you use synthetic but what about simi synthetic?. I will be taking my cylinder in to a machine shop to get it deglazed and thanks for your help

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you use what oil your going to run in it ... just stick with full synthetics choose one and go with it.. don't change your pre mix ratio or anything you break a bike in like you ride one !!

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you use what oil your going to run in it ... just stick with full synthetics choose one and go with it.. don't change your pre mix ratio or anything you break a bike in like you ride one !!

+1 chose a good oil and stick with it , I perfer honda hp2 , ran it for ever outstanding product 32:1 , don't get concerned with break in just go ride it!!!

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I need an oil that's cheap and available at a local auto store,what do you think about lucas semi synthetic?. is honda hp2 a synthetic oil? I didn't think that it was.I tried the scotch bright pads after reading more on nikasil plated cylinders but it won't break the glaze so I'll have to take it to a shop to have it deglazed.anyways thanks for your replys

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its like $7 a pint i think out here enough to do 5 gallons at 32:1... i run H1R/ super "M" ...and HP2 before this top end .. i just wanted to try something new .... im convinced H1R is the same thing as super "M"

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its like $7 a pint i think out here enough to do 5 gallons at 32:1... i run H1R/ super "M" ...and HP2 before this top end .. i just wanted to try something new .... im convinced H1R is the same thing as super "M"

i just whip accross the border for the weekend do some shopping and pick up a case ,which last me the year and especially with our dollar being so strong $1.05

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okay I got my oil and my wiseco top end came in the mail yesterday,I set the ring end gap and everything is looking good so far.couple of questions though do I need to drill holes in the piston? it says you have to if there is a bridge in the exhaust port so is this a bridge? it may be a stupid question but I like to make sure and check twice before everything gets put together

http://www.thumpertalk.com/forum/garage.php?do=viewattachment&attachmentid=92971&thumb=1

next question do I have to have a seal between the exhaust manifold and the expansion chamber? if so what can I use it had nothing when I bought the bike, I was thinking I could make a temporary seal out of something like high temp silicone but it's only good for up to 650 F so what would you suggest? I'm going to hold off on putting every thing together until I get money for gas that way I make sure every thing is well lubed before the first kick.thank you for all your help and I will keep updated.

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oh and also the inner diameter of the head gasket that came with the kit is a little bigger than the one I took off, it still bolts on and every thing but it's bigger than the cylinder bore just want to know if that'll hurt anything what do you thank?

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I'm doing my first top end and I need some suggestions on what oil to use for break in. Is lucas simi synthetic racing oil you get at O'Reilly okay to use?

Lucas 2-stroke oil is excellent. It's fairly light so don't go over 32:1

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I'm not big on hondas but that looks like the exhaust bridge to me. Look through where your pipe goes into the cylinder.

100_1906.jpg100_3115.jpg

There's an exhaust bridge for ya!

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okay thanks I was just making sure because I heard somewhere that they didn't have bridges on the older models, but I guess they do so it looks like I'm going to be drilling some holes. I will be making a build thread with pictures when I get everything done and thanks for all of your help

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okay thanks I was just making sure because I heard somewhere that they didn't have bridges on the older models, but I guess they do so it looks like I'm going to be drilling some holes. I will be making a build thread with pictures when I get everything done and thanks for all of your help

Make sure you use a new and high quality drill bit and closely follow the directions given with the piston. A table vice is nice to use if you have one (don't over-tighten it, and put a shop rag between the piston and the vice), that way the piston won't move and make you walk your drill bit all over your new piston... Also, some people suggest using a center punch to score the spot where the hole will go, to give your drill bit a little bit of a path to follow, so to speak. I don't know if this is necessary if you start slow and steady and are familiar with a drill... Good luck man! :thumbsup:

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Make sure you use a new and high quality drill bit and closely follow the directions given with the piston. A table vice is nice to use if you have one (don't over-tighten it, and put a shop rag between the piston and the vice), that way the piston won't move and make you walk your drill bit all over your new piston... Also, some people suggest using a center punch to score the spot where the hole will go, to give your drill bit a little bit of a path to follow, so to speak. I don't know if this is necessary if you start slow and steady and are familiar with a drill... Good luck man! :thumbsup:[

I drilled them at about 4:30pm but they came out pretty good I didn't mess anything up but thanks for the info I'll remember on my next top end:thumbsup:

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I was going to suggest that you install the piston on the rod without the rings, then install the cylinder and use a Sharpie to mark the piston on each side of the bridge to assure that you drill the holes in the correct location. If the holes don't line up with the bridge, you will lose crank pressure out the exhaust on the downstroke of the piston which will affect power.

This is one of the things about Wiseco pistons that's really hokey.

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