Rebuilding engine... suggestions for ideas and parts?

[pac00t]

Hi, I'm rebuilding my 79sf. I found a good machinist who will do the work, but I have a slew of questions. Any help would be appreciated!!

I'm having the valves seated. The guides look shiney, so I think I will just replace the seals. By themselves the seals are expensive, but there are some gasket kits on ebay that advertise that they include the seals. The kits range in price. Are some better quality than others?

The pistons/cylinders are at the wear limit for each. Pistons and rings are std size. The rings are worn, so I have to choose whether to get std rings ($120) or WisCo.

Also, has there been a determination whether OS 1 rings will be ok with std pistons?

Has anyone had problems with the crank? Is replacing the bearings a good idea?

Thanks for suggestions.

As for parts... Anyone got an extra exhaust valve for a 79 laying around?

[Snow]

If the bearings are worn, replace them...but how do you know if you don't pull the motor and split the cases? If you split cases, definitely replace crank seals and starter clutch bits. I needed to replace my crank seals and starter clutch bits...then once I cracked the cases apart, found out my crank bearings were shot too :/

Buuut, if all you really need to do is cylinder work, it's a lot easier without splitting the cases. Wiseco kits are still made new and I just ordered a set of rings for my bike (long story, don't wanna talk about it else I'll start yelling at myself).

If you are going to the trouble of boring, you might as well get a wiseco kit for a couple hundred more imho.

[mro]

Have used differerent gasket sets.
No problems reported.

This set $77.00
https://www.partsnmore.com/cat_index...ategory=engine

Crank seals do not come with gasket set.

Can plasti-gauge bearings. If any question if in spec or not would change. Just crank bearings can run over $100.

Would change cam chain too.


mro

[TopCatGr58]

Hey Pac,

Ken Talbot has done the 1st OS rings on standard pistons, but can't remember if he BORED it to 1st OS or just HONED it? It has worked for him for several seasons now!

As for the gasket kits, the PNM should be just fine!

Please post a separate request for parts in the FOR SALE/ ITEMS WANTED FORUM!! See below for NEW PRICES!

What's the mileage on this machine? I had over 50K on mine, and did just the topend rebuild some 6 years ago, has run just fine, didn't want to split the cases, and didn't think it was needed since it was running just fine prior to it's hibernation for 9 years before I got to back to it!

I see now MRO has posted a reply, forgive repeat info!
T.C.

YAMAHA XS1100 (78-81) GASKET SET
Fits: Yamaha XS1100 (78-81), XS1100L (80-81) Midnight Special, and XS1100S (79-80) Eleven Special.
39 piece, Top and Bottom End Engine Gasket Set. Includes valve seals and all O- rings.
High quality. Made by European OEM supplier.
This is the Most Complete Gasket Set Available from the Aftermarket.


$77.00US /Set

Part#18-0160

OR...you can get just the valve seals at this price
VALVE STEM SEALS
Fits XS1100E/F/SF/G/LG/SG/H/LH (78 - 81) Made In Japan

$3.00US EA.

Part#01-0136

**Best part, PNM gives FREE SHIPPING for orders > $35.00!!! either thru their web site or the Ebay Store!

Exhaust Valve: 1J7-12121-00-00

Bike Bandit: 2: VALVE,EXHAUST 7367-001 $48.62

Cycle-Parts.com has it for $43.51, BUT they require a $100.00 minimum order!

According to MrCycles.com 12R-12121-00-00 replaces above at $38.35!

[Snow]

I forgot to mention, I have a few lipless left crank seals left (pickup coil side) and am selling at cost plus shipping (cheaper than bikebandit, etc).

I got my right one from bikebandit within a couple days but the left one was on backorder close to a month...

[79XS11F]

Note .. Just because the valve stems are shiny does not mean they are good to go. If your doing new seats then check the specs on the stems while the head is off. Clean and polish the combustion chambers while the head is off as well and confirm valve springs are within specs.
Order up a gasket kit that will include most if not all of the little O-rings that will be required if you split the cases now or in the future.
Change out your exhaust studs while your at it.
As for Yamaha oversize or Wisco .. Go Wisco Because the total difference in cost is not a lot and the labor involved except for the actual boring to Wisco size is the same for both jobs.
That's my 2 cents :-)
Rob

[pac00t]

Thanks guys for all the help.

[MAXIMAN]

PAC

I bought a set of Athena gaskets ($60) and sorely regretted it. The valve seals that came with the kit were sub standard.

My base gasket started leaking after 4000 miles. And the valve seals were too.

I replaced the base gasket with an OEM and put OEM valve seals in and my oil consumption went to zip. The material that Athena uses is not as durable as others.

It depends on the gasket kit. If it is OEM or K&L it's probably ok. But Athena is no good IMO. I bought that kit from partsnmore.com. Just my experience...YMMV.

[John]

Vesrah makes a very good gasket set. Very complete, except for the half moon plugs for the head/valve cover.

[MAXIMAN]

Does anyone besides Yamaha make those (half moon plugs)?

[John]

I have seen them on ebay, but they weren't cheap. I got some from Bike bandit, last year, and they were not expensive at all.

[Snow]

Partsnmore also has 'em..for some reason I think they *might* be different from 78-79 and 80+

[TopCatGr58]

The Half moons from PNM are for all years. I've got an 81, and they fit and seal just fine!
T.C.

[79XS11F]

To date I've never had an issue with them mine leaking ... knock on wood
Rob

[Czekus21]

I just ordered a set of half moons from Bike Bandit. $4.00 a piece.