Big bore

[desert1]

What mods need to be done to the head of the engine, valve guides, valve springs? Besides pistons, rings and sleeves, and gaskets ....big bore time .
Bruce

[DiverRay]

Bruce,
You can run it with just a valve job, and new valve seals on the head. With more MONEY, you can have the heads ported to flow more air, chambers "CC'd" and valve stems polished. It just depends on your wallet, or what you can do yourself.
Ray

[MAXIMAN]

Bruce

I'm in the process of doing a big bore to my Eleven...and then some.

Like Ray says you can gain quite a bit by just overboring...but I'm going to do a bit more than a bore. Port the head, radius valve job, Web cam, and header.

[dewibp]

Hey Maximan, what do you think you have in just the boring and kit only? thx dew

[TopCatGr58]

Hey Dew,

The big bore kit is still attainable from Pro-Flo in Fla for under $400.00, and I was just at my local machine shop, and they still only charge about $40 a hole to bore it. I did the head work on mine myself, but just lapped the valves/seats, and replaced the seals, didn't do any porting or polishing. Works well, but if you've got the pockets or time, you can wring more power out of these machines, however the big bore gives it plenty of kick alone!
T.C.

[desert1]

its really time

Thanks for the replys Guys, I really dont want to part-out or part with my eleven that why I'm lookin for the help online......you have these bikes for so many years and you learn a lot about them, lately I've learned its goin thru more gas than it should. 29 per gallon along with a lot of engine clatter and perhaps some cam chain noise, one cylinder is down to 90 psi, the highest is 125, so its time.....so its parked until I order the kit and then I will tear down the engine, perhaps I can get some riding in yet this year! Again thanks for the tips and pointers to you all and big Hello to TC!, been awhile since the "Thunder in The Islands"
Bruce
78XS1100 Alpha

[MAXIMAN]

Dew

I bought my kit from ProFlo two weeks ago. I paid $367 plus S&H

I noticed about 3 or 4 days after I placed my order they upped the price to $408. Here's the link: http://www.pro-flo.com/pro-flo_wisec..._bore_kits.htm

My dealer is actually doing the bore. He's charging me $150 or 200. So If you're willing you can do it yourself for less than a grand.

However...Cody "ain't" willing. I simply don't have the time.

I trust my dealer. He has done good work on my ZRX. He has been racing and building Yamaha air cooled inline fours for about 20 years (FJ1200 in Legend Cars) and seems to be very competent. So he's doing all the work...overbore...ported head...and installation of all parts(cams, header, etc) and tuning.

His shop has a DynoJet 178 dynamometer so we should be able to get the tuning on the money.

[mro]

shop has dyno

Way cool dude...

Been waiting to see some numbers for what the BIG bore kit can do.

you are gonna post em????
please



mro

[MAXIMAN]

Heck yes I will post the results. I can't stand the thought of spending this much money and not bragging a little!!!

However we won't dyno the bike until we are doing the final tuning so we won't see the gain from the Wiseco kit alone. The dyno run will be after all mods are completed (head work...ported and radius valve job, piston kit, Web cam, header and re-jet).

Hopefully he'll be rolling the big Maxim 1200 out the door in a couple weeks. If we don't see close to 100 hp and 70 ft-lbs I'll be disappointed. As well I should be after spending a small fortune.

As the crazy blind man once said "We shall see...we shall see."

[GNEPIG]

However we won't dyno the bike until we are doing the final tuning so we won't see the gain from the Wiseco kit alone. The dyno run will be after all mods are completed (head work...ported and radius valve job, piston kit, Web cam, header and re-jet).

.. hopfully we wont see any dyno results until after you have finished breaking it in properly and givin it a proper service..

[Pat Kelly]

OK I'm getting bored here

I have the funds squirrelled away. I'm going to order the Weisco big-bore kit for my Midnight Special.

The bike has 60,000 miles on it. The little filter that covers the drain in the airbox has been missing since before the bike came to live with me. So, it's been sucking in unfiltered air for a long time. It smokes when I 'git onnit' and it also smokes when decellerating. Thankfully it dosen't smoke when it's parked.

My delema is if to buy the 1174 or the 1196 kit. I know, with the 1174 I can always go to the 1196 when the 1174 is worn. Well the stock bike has lasted 60k miles and 28 years. In another 28 years I'll be 75 years old and internal combustion engines may be outlawed.

I have a spare set of cylinders that the kit will go in so this winter it will be a quick swap (unless I pull the motor and do a complete repaint). New stem seals and matching the intake ports are the XStent of what will be done. I'm also moving my oil cooler from the E to the LG. Stock airbox with K&N, 4 into 1 (modifyed to 4 into 1 into 2 later).

So, 1174 or 1196? What da y'all think????

ps. The kit comes with a head gasket, do I need a cylinder base gasket too?

[MAXIMAN]

I say go for the BIG UN.

If you have an extra block like me you can always go back to OEM.

I don't think the 1196 hurts anything. The Eleven is overbuilt to begin with so taking it to 1200cc is no big deal. After the bore the bottom of the cylinders is still 2.25mm and even thicker up top as the sleeves are obviously tapered.

WARNING WILL ROBINSON!!!:

Don't be fooled into thinking you get 10.25:1 CR as advertised by the WiseGuyz. The piston profile is identical to the OEM as is the wrist pin offset. The crown on mine measured about .002 taller which in real terms is nothing.

You will gain a good amount of compression simply from overboring but not from an increased piston crown. So to make it up we shaved my head .018.

Dan thinks my actual static is about 9.8:1. That beats a poke in the eye but it still ain't 10.25. Wiseco has never honestly answered how in the heck they arrive at 10.25 to 1. I even had a Wiseco technician freely admit that the crown of the 1196 and 1179 were profiled after the OEM piston. However he tried to tell me the wrist pin was offset to make up the diff.

I call BS on that. Like I said before when we line the wrist pins of the OEM and the Wiseco the Wisepiss was about .002 taller (cork POP! woop-dee-do).

This is why I would have no qualms about going to an 1196 kit. The only thing to fear is heat from resulting compression. Since we know ya ain't gonna be at 10+ then there is really nothing to fear.

If you actually cc your heads, pistons, and gaskets...the numbers just don't add up. If you do nothing but the Big Bore you'll likely see 9.5 or there abouts

[MAXIMAN]

PS...yes you'll need a base. I just bought the whole bananna at partsnmore...a engine gasket kit for $65.

[Pat Kelly]

Knowing compression will be (relatively) stock is a plus in my case. This bike is mostly for (spirited) commuting and the Tahoe rally.

[MAXIMAN]

My sentiments exactly. Acheiving CR in XS of 10:1 can present some real problems on an air cooled bike.

One of the hottest air cooled bikes was an FJ1200. The thing was making about 115 or so at the rear wheel. But Yamaha had enough wisdom to keep it at 9.8 to 1. Yeah yeah there are references it was higher...but those references are either vomit or some crap the marketeers at Yamaha jinned up.

I've never owned an FJ but several friends have and they all report pumping compression on the order of 145 to 150.