Yosh build part deux

[first timer]

SO lets see if I can keep this up, I am running a parallel post over at http://www.oldskoolsuzuki.info/

So some of this will just be copied and pasted

You have been warned!

Here’s my deal, I have been planning a GS1000y build for a while now, first phase was to get the bike working and cleaned up with the idea of building it into a replica racer.
Here are a few pics of what it was and what I got once I was done.









Now it's time for phase 2, the engine build. This is my first build so please be patient with me; it’s going to be a big learning experience and project for me. To help guide me I have been working with Speedy Steve (he is a great guy plus he is only an hour and a half from me). We are looking at doing a stage 1.5 build that is easily expandable for future competition use. We are trying to use most of the stuff I have right now (yosh 1085 kit w/11.2:1 cr, oem exhaust valves, vm29 smoothbore carbs, yosh 4 into 1 2.5” dia header w/ canister or a yosh 4 into 1 3.5” dia header w/megaphone, accel coils, some basic things like that)

Basically this is my plan for the motor: ported head, 1085 kit, going to get the crank rebuilt by Falicon or Gardner Racing Concepts, keeps stock rods, having crank guy inspect them, I was thinking about going straight cut primary, gotta see what I am quoted first, a gs1100 billet basket (still researching this, I think I just need to cut it down a bit to clear the inside of the cover) I might get the gears undercut locally, got to see how much that is and what shape the tranny is in, going to run a msd mc-3 box based on Steve’s recommendations and last but not least paint the motor in kal guard gun kote to help with heat.

This is my basic plan and will grow change as I go.
Some immediate questions I have are in regards to my head, since Steve is almost done with it.
I need some new intake valves, I was thinking stock size SS, but am having a hard time sourcing some. Steve likes Ferrea valves but they don’t have any GS1000 valves. They would do custom but I need to get them the specs (anyone have exact specs so I don’t need to mail them a new oem intake valve). Kibble White and APE were options too but they don’t have any listed either, who have you guys used in the past? Any part numbers?

I have new oem exhaust valves I got a deal on so I am going to run them now to be cheap.

I am going to replace my guides with bronze ones, found some from Kibble White, what do you guys think? Anyone else you like?

For now to save a few more bucks going to run the biggest cam I can without going to under bucket shims, which I think is a web cam grind 110. I was going to get some web cam HD springs. Should I go to aftermarket retainer? Alum? TI? or keep oem for now?

I want to get my head built right so I am not spending extra money in the future I didn’t need to. Does anyone have any comments or suggestions? Any recommendations for the little bits like HD head nuts and such?

I am going to focus on the head for now, once that is almost all put together I will work on the other stuff on the list.

Another thing while the engine is out I was thinking about doing some bracing, do I need to follow the diagram for bracing you guys have posted? I guess what I am asking is what are the most important points of the frame to brace?

Thanks guys
-Ryan

[first timer]

I am still on the hunt for valves, talked to Buzz at dynoman, he has upped his prices to $47 a pop now minimum order 8. I going to run stock size valves for now since I already had my seat recut for stock size. Steve thinks stocks size is best for street.

I see that south african site but i can't stop myself thinking it's some sort of scam. Anyone deal with them before? They seem to be using good materials. I guess if i go that route being out +/- $100 isn't that bad if i am going to gamble.
Maybe i can find a S. african friend to investigate this further.

http://www.sportflo.co.za/Custom%20Street%20Performance%20valves.html

Talked to stan at gardner racing I am going to have him do my crank, he is priced fair and seemed like nice guy over the phone. I am going to bite the bullet and have him throw a straight cut gear on the crank too. Now i just need to figure out if i can get a gs1100 billet basket to work or try having stan reinforce the stock gs1000 basket.

I going to run the stock studs as well, maybe just get some new ones. Keep the valve ideas coming. Anyone got a source for cheap oem valves if the SS valves are a bust?

-Ryan

[first timer]

Mmm nice and shiny, I picked my head up from Steve last Friday, It’s looking real nice, good quality work you can tell he put some hours into it.










So now on to my next adventure, going to pull the crank this weekend and get that sent off and am going to send my cylinder off as well to get bored out.

While I have the bottom half all pulled apart I was going to look at the transmission, see what that looks like, anyone have any tips of what and where I should be looking for trouble?

I am still wading through valves trying to source some for a decent price, everything seems to be around $45 per valve. I might give that S. African website a try, I have been asking around to some S. African guys and they all have had good things to say. Here are a few email replies I got back:

“The feedback I got from two guys I know that race bikes in the nationals are that the parts for the bikes are very good and they have had no hassle’s at all. You can go ahead with confidence. Kirk Brooks”

And

“The company is reputable, it is owned by a very well known gentleman by the name of Steve who owns Steves Auto clinic. They do the normal vehicle servicing as well as engine tuning and modifications etc so it was a surprise to me that he owns this company. Steves Auto Clinic is reputable i have never used them as i do my own work but i know of people who have used them. They are quite expensive though. Hope this helps. Hey i thought you guys had warehouses of parts and accessories in the states. Let me know if i can help you out further.”
Best regards
donovan gould”

So now I just need to shoot Sportsflo an email and see if they can even do these valves for me.

Anyone have any leads on valve seals? I was wondering if there is an alternative to the OEM seals, like some sort of vitron seal or something. Kibblewite has some for the old Z1 (see pg 78 of their catalog) and valve guide diameters compared to the gs1000 are the same (see pg 118) just not sure about the length of guide where the seals mount on to would work. Might have to call. The Z1 and the GS have the same valve diameter as well, so that’s not a problem.

Ok back to my searches and comparisons

-Ryan

[Nessism]

Don't understand what your hesitation is regarding stock valves. Suzuki used top grade materials in their engine bits which is something that can not always be said for aftermarket parts. Stainless is not the most wear resistant material around so the valve stems have to chrome plated to get reasonable wear resistance. Give me stock valves over cheap stainless valves any day. High quality stainless valves are viable but at what cost?

[bwringer]

Don't understand what your hesitation is regarding stock valves. Suzuki used top grade materials in their engine bits which is something that can not always be said for aftermarket parts. Stainless is not the most wear resistant material around so the valve stems have to chrome plated to get reasonable wear resistance. Give me stock valves over cheap stainless valves any day. High quality stainless valves are viable but at what cost?

That is one tasty-looking cylinder head...


Anyway, Nessism echoed exactly what I was thinking -- it didn't appear you had done anything hugely radical with the head or porting, so I was kind of wondering why exactly you didn't want to use stock valves. Plus, aren't the valve seats already done? Are the new valve guides already in there? Unless you're using bigger valves, why not use OEM?

The toughest valves you can find are probably going to be stock, and Flat Out lists the OEM intake valves at just $22.88 each. Such a deal.

As far as valve seals, is there some reason you don't want or can't use stock? They work pretty dang well for many years, and they're already made from Viton or something similar. Goodson sells a wide selection -- they have 7mm Viton seals in packs of 20 here:

http://www.goodson.com/store/template/product_detail.php?IID=5573&SID=969f3156eb92b49589aa5d13013df74f

New stock cylinder head studs and nuts should be plenty strong. APE sells stronger ones for GS1100/1150 dragbikes, but I don't think they have them for the 8 valvers. Unless you're running nitro, I don't think you'll have a problem. You might poke around with APE and Schnitz and see if they have any upgraded bits. However, lots of stuff even on the most radical dragbikes is Suzuki OEM.

Also, I'd seriously consider brand new OEM shift forks while the engine is apart, just because. You could skip this if you haven't had the slightest problems with shifting and the wear pads on the ends don't look worn in the slightest.

Maybe I'm talking like the fat shaftie rider I am, but I basically prefer to build things bulletproof -- the first priority is to finish the race or ride. That generally means stock parts unless there's a compelling reason to do otherwise, as with your big bore kit, carbs, and cams.

I wrenched on a buddy's race bike for a season, and 90% of the battle is just finishing races upright and running.

[first timer]

I appreciate the feed back from both of you. My main reason going stainless is OEM costs about as much as SS. Also with stainless you get a lighter valve, you can get valves in many different shapes one's with undercut stems and coatings for better flow and so on. If the OEM was so good why wouldn't aftermarket valve suppliers / racers be using that? I am not expecting to get 100,000 miles out this motor, this is more of my hotrod bike something that you are always tinkering with, if I want a factory bike then I can take out the SV or the KAT.

Yes the seats have already been cut for OEM sized valves, so I am going to run that size, I am just trying to explore the valve route thoroughly, my stock valves are in good shape and can be reused if I do go that route. I need to get a parts list together so I can start making decisions based on money as well.

I still need to replace my guides, like I said want to go bronze but am holding out until I see what I am going to do with the valves since there are variations in guide sizes to choose from and those need to relate to the valve stem OD.

I will probably go with factory seals but was just trying to see what my options were, technology and material science does change.

The ports have been opened up a bit, from 28mm to 30mm, this head was designed to be a high velocity head vs. monster flow head with the ability to go to a oversized valve in the future.

The more I think about it I will be using the OEM studs, just new ones, they were good enough for POPS on his bikes, plus I am not sure I like the idea of the oversized ones especially in the oil passage, restricting the factory calculated oil flow.

Thanks for the tip on the shift fork, I was thinking that they aren't to expensive for a piece of mind. The ignition system I am going run should help protect the motor with a rev limiter built in, in case of a missed shift. After it's all said and done this motor should happily turn 10k rpms and that’s what I am trying to select parts based on.

[Nessism]

The valve seats are typically cut using the valve guide...as a guide - arbor fits into guide thus definining the exact center. If you remove the guide doesn't that potentionally invite out of alignment concern with your freshly cut valve seats?

Regarding stainless valves being lighter, this will be true if there is less material in them - such as undercut valves. Just make sure any stainless valves you get have chrome plated stems since stainless will wear faster than the OE valves unless the stems are chromed.

Good luck. Looks to be a fun project.

[first timer]

The valve seats are typically cut using the valve guide...as a guide - arbor fits into guide thus definining the exact center. If you remove the guide doesn't that potentionally invite out of alignment concern with your freshly cut valve seats?

Regarding stainless valves being lighter, this will be true if there is less material in them - such as undercut valves. Just make sure any stainless valves you get have chrome plated stems since stainless will wear faster than the OE valves unless the stems are chromed.

Good luck. Looks to be a fun project.

I don't know like i said this is my first build. I'll run it past my tuner since he was there when they cut the seats, We were going to lap the valves and seats anyway so shouldn't that correct any mis alignment? (I know what the manual says about lapping...)

[Nessism]

Lapping is good for removing surface contamination on the valve and seat but it should not be used to define the fit between the parts. That's why Suzuki warns against lapping; it's commonly incorrectly applied.

[hampshirehog]

Lapping is good for removing surface contamination on the valve and seat but it should not be used to define the fit between the parts. That's why Suzuki warns against lapping; it's commonly incorrectly applied.

Just a check on the translation - in the UK we would 'lap' = grind very gently with the fine paste to restore the seating to 'perfect' from 'not bad'.

We would 'grind' = grind with the coarse paste (follwed by lapping with the fine paste) valves that were badly pitted etc.

Is that what you guys mean?

[Nessism]

Just a check on the translation - in the UK we would 'lap' = grind very gently with the fine paste to restore the seating to 'perfect' from 'not bad'.

We would 'grind' = grind with the coarse paste (follwed by lapping with the fine paste) valves that were badly pitted etc.

Is that what you guys mean?

Not exactly.

Lapping is a process where the valve is installed into the head with some grit on the face and the valve is rotated to abrade the surface between the two parts. It doesn't matter what grit you are using, it's still called lapping.

Lapping should only be done to clean up minor imperfections in the valve face or seat or to verify the seat width is the proper...width. If there is significant wear on either the valve or seat, lapping is not applicable; the parts should be properly reconditioned with machine shop tools.

[hampshirehog]

Right, I'm with you now and agreed. I would lap the valves in no worries over here but I wouldn't grind them - it's just a matter of degree.

[bwringer]

As far as the studs, does the BB kit call for increased torque? (I can't imagine why, but just askin'.) I'd put in new OEM studs and nuts, anyway. That's what I did on my GS850, and I think you get more accurate torque with nice clean new threads. And they're purty, too.


Is the limiting factor in RPM the valvetrain or the connecting rods (with the bigger slugs attached)? It sounds like you're going after the valvetrain mainly. Is that the usual GS weak point?

By way of comparison, the redline on a GS500 is 11,000, and it uses the same valvetrain design. The springs are a different part number, but I don't know if they're heavier or what.

Very interesting... keep us all posted!

[long_av8r]

First Timer, the bike is looking awesome. I can't wait to see the finished product! Keep posting!

[BadBillyB]

Hey Ryan, cool engine build. Just wanted to help if I can.....

If your going to stay with the stock shim on top set up....Your goal should be to end up with the thinnest shim possible to keep the valve train weight to a minimum. This will give you reliability at high revs. The stock Suzuki intake valves are 38mm and are not only generous in size but give good service. If you go with S.S. aftermarket valves, they must be perfectly made to give the correct amount of spring pressure (based on keeper location) and enable you to use a thin adjustment shim. I personally have used Star Racing in Americus Georgia to make custom valves before but that was long ago. Jay at APE in Cali should also be considered as his shop is awesome and he knows GS1000's.... When you get your Web-Cams, take a stock valve, put it on the seat (with no spring)...put a stock bucket on it with the thinnest adjustment shim in place and see how much clearance you have.....custom made valves require a lot of math (measurements) to get great results.......Billy