1179 or 1196 Wiseco Big Bore Kit: Worth it?

[Shuriken]

A. Do you feel that the performance improvement from installing the 1179 or 1196 was worth the time and costs involved?

B. How much HP and torque do you know you gained or believe that you gained?

C. How much did it cost you for the upgrade (time, parts, labor, etc.)? This should include the cost of the kit, labor cost, additional costs for gaskets, jets, etc., but not the cost of things like new carb filters, exhaust pipes, porting, polishing, etc.

Thanks,
Ben

[Pat Kelly]

The only reason(s) I did the BB kit on my MNS was:
a- It had 60,000 miles on it and,
b- It had the filter missing from the drain hole in the airbox. Who knows how long it had been sucking in un-filtered air. The bike was smoking badly, I was assuming worn rings. And,
c- It was smoking on both accelleration and decelleration. Rings and valve stem seals were leaking.

Before the BB kit my E was faster and quicker than the LG. Now the LG is quicker but the E still has a higher top-end. I attribute it to the difference in size of the rear wheel.

Parts-wise I had the BB kit, gaskets, seals. I did some other work on the bike while it was down. Parts was around $600 or so. Labor of boring the cylinders was $160.

I spent more on the big-bore than I did for the bike ($500 for the bike). Keeping the bike on the road, priceless.

The original head has issues so I am replacing it. I have a 78 and 79 head/cams assembly comming. I will detail the nicest one. No port and polish, just have the castings cleaned-up. This time I will replace the timing chain and go through the carbs again (reducing the main jets fron 125 to 120, 125 was just too rich). Also replacing the clutch as even now the bike is over-powering it and it slips when "gitting on it", that wasn't an issue before the BB kit.

As far as if it was worth it, I don't plan on doing the BB kit on my E unless it needs it. The LG needed rings and oversize aren't available so I went this route. I decided on the 1196 kit because it cost the same as the 1174 kit. I figure the original lasted nearly 30 years. In 30 more years they may outlaw internal-combustion engines so it will be a moot point. If need be I still have the original cylinders that can be bored also.

[TopCatGr58]

The Little Big Bore Kit!

Hey Ben,

Mine, too, was a matter of necessity than desire! Had left the bike outside for many years, improper prep of engine, moisture, etc., lots of rust in cylinders, estimated 50+K miles on engine(broken Odometer on OEM gauge at 970 miles ) needed to bore to get clean, standard oversize not available, decided on 1179 due to allowing thicker cyl walls, and room for the 1196 bore IF ever needed! However, I could probably find a set of old stock jugs and just rebore to 1179 with new rings and reuse the 1179 pistons IF I had to!

7 years ago, ~$450.00 for BB kit, $160.00 for boring job, did the head myself, lapped and replaced oil seals. I bought individual seals instead of complete gasket kit since Head Gasket came with BB kit, made most of my other gaskets! Aside from the Bore, did all labor myself, so "FREEBIE"!!

As for power/torque, can't really say, hadn't ridden it for 9 years prior to rebuild, but I'm estimating a 10-15 hp boost based on what I've read that stock was around 65 at the rear wheel, my dyno results showed ~78hp rear wheel, but only 56 ft/lbs torque!
YMMV! I just know that it's plenty powerful for me!
T.C.

[mro]

worth the time and costs

Really boils down to what your looking for...
Want to go up aginst a R1, no

Keeping a classy clasic XS on the road and bragging rights here you have a winner.

PO spent way more than just a big bore kit on a G I have. (Well it does have an 80G frame) It's possbly the fastest XS11 short of a turbo on the road today. But today I would not build such a motor for an XS, BUT if I didn't have the parts to rebuild one of my 11's would spring for the 1196 kit for same reasons as Pat.


mro

[TADracer]

Considering the cost for the few extra HP I do not think I would do the conversion unless it was required to keep the machine on the road (or if money is no object). Consider the cost, $600.00 for 10 HP +/-. $60.00 per HP is a bit on the pricey side for a 30 year old machine unless, it is an XS and needs the modification to keep running.

Now, if you really want to spend money and find some real CC's, stroke it.

[MAXIMAN]

Ben

Ya gotta be careful with this big bore kit and the Eleven. The stock...off the shelf kit from Wiseco will NOT yield the anticipated results on 1980 and later motors.

The 78-79 motors had smaller chambers and small dome profile on the pistons. The 80 and later motors had larger chambers and a larger dome to match the chamber.

The Wiseco kits were designed for the early heads. The only way you'll get anywhere near the 10.25:1 static compression is using the kit on the 78-79 head. If you use it on the late heads you'll actually wind up with LESS compression than stock! That's because the late head chambers are much larger than the Wiseco piston profile.

However...Wiseco will cut a piston profile to match the late heads for the 1196 or 1179 big bore kits. But it cost a little extra.

So in short...I would say yes to the question IF you are installing a shelf kit from Wiseco on a early motr....OR if you install it on a late motor and shave the head 25 or 30 thousandths.

But NO...if you install an off the shelf kit 1179 or 1196 with a late head. You wind up with 9 to 1 CR or less.

If you search around here somewhere Trbig posted some photos of the late vs early piston profiles. The difference is plainly obvious even to the naked eye.

One more thing. A very slick trick for increased compression is to couple an early head with the late pistons. Theoretically this will result in an increase in compression on the order of 10.5 to 1.

[AlanB]

Hi Guys,

I have five various XS11 motors, plus a couple of loose heads; I should have the bits to do a high-comp motor, but I am not sure how to identify what I need, without stripping 'em all down and spending some time comparing them visually.

Are the heads marked externally as different, or do you need to strip and measure?

Can early and late motors be identified from outside?

Are the barrels (Block?) the same on early and late motors?

Thanks guys!

AlanB

[mro]

serial #'s will let you know what motor you have.


mro

[trbig]

If the motor is stock, the part number stamp over the crankcase oil filling area will have a part number starting with 2H7 if it's an early motor.

If you have the heads loose, there is an obvious difference in the valve sizes you can see with your eye. the cylinders are all the same size, but if you happen to have an 82 head or cylinders, it will have the YICS stuff on the back side.

Just a word of warning though. Bumping up your compression to anything above 10.25 to one will result in you needing better fuel. 10.5 to 1 may require you to use other than pump gas. Some can but some can't... don't ask me why.

Wiseco will cut a piston profile to match the late heads for the 1196 or 1179 big bore kits. But it cost a little extra.

Where were you a couple weeks ago when I was ordering these?!? Thanks ol' BUDDY!!

Oh well... I'm the type of guy that may do a little better with a little LESS power.. lol. I want the thing to hold together for a while and more power is too tempting to me. Hippie Dave keeps telling me I need to come ride his Bussa... I keep telling him No, I don't! lol.


Tod

[AlanB]

Hi trbig,

I got a lot of numbers, but no 2H7.... mine are all euro or Specials! I guess I will have to try to find the valve sizes and work from there!

I think the motor I am running is an "early" 'cos it has a kicker shaft, so it will not be as easy as a head swap.

AlanB

[mro]

UK XS11 site should have info for the EU models

click

http://www.benefiscal.co.uk/forum/index.php?PHPSESSID=f435091e5708389f76e517c574a54e78&

mro

[trbig]

so it will not be as easy as a head swap.

Why not? It would work. I don't know of anyone that has actually gotten the listed numbers (Compression 10.5 to 1) by just installing this kit, but I guess it could be possible.


Tod

[AlanB]

Hi trbig,

What I meant was that if I was running a late motor, it would only need the early head dropped on to give the raised compression. Since I have the early motor, I would have to either resurrect one of the other motors and add my present head, or strip a later motor to get a block and pistons to swap into the present motor; either way, it means messing with (at least!) two motors; not one.

AlanB

[TopCatGr58]

Hey Tod and Max,

I did the 1179 on my 81, keeping stock cams/valves/heads.

Stock 142psi divided by 9.0(later model ratio) = 15.77

15.77 x 10.25 = 161.72

Taking the allowed +10 value of 152 psi / 9.0 = 16.88
16.88 x 10.25 = 173.11

I got 180-185 psi on mine after breakin, and I'm pretty sure it wasn't due to carbon buildup, especially the way I like to run it in the higher rpms!

How do you/we explain these results IF I'm not getting the 10.25:1 comp ratio even with my later model engine?!
T.C.

PS...I didn't shave the heads, BUT I did use their Cometic graphite head gasket, and perhaps it's a little thinner than the OEM style??

[Pat Kelly]

The stock head on my LG (1980) has issues at cylinder #2. I got a complete head and cams from a 78 that I am going to use.
Just as a thought, could the smaller valves of the earlier head increase the velocity of the intake charge? The volume of the charge may be less but it wil actually flow faster.
Just tossing out a theory.