Heavy duty timing chain

[gsryder]

What size spacer are you thinking of putting in there? I think your big problem will be needing a longer cam chain (and maybe longer studs).

There was an article in one of the mags about mixing and matching 86-90 GSXR750 cranks, rods, etc. to get a long-throw motor, and they needed a spacerplate/camchain for that (made by Falicon?). I think they claimed it was the highest horsepower 750 they ever dynoed. I can probably find the article (up in the attic).

Are you making your own plate? If it is made by someone, they can tell you what you need.

They used to make low compression pistons for turbo applications.

I am not sure on the spacer size yet I dont need to lower the compression much. Stock they are 9.5:1. I think I want to get down just below 9:1, I will have to do some math and figure out what size base gasket I need to order from cometic. I could be wrong but I dont think the base gasket thickness will be substantial enough to effect the stock cam chain length.

I am still working out details and gathering parts. So far I have all the major components - Katana front end, GSRX rear swinger, 1100 engine, Turbo from a 1.8liter Audi A4, all going on to my 1981 gs750 frame this winter. I will starting a build thread once I actually start putting the wrench to her, for now I am still gathering parts and info.

 

[doctorgonzo]

Why do you want to drop the compression slightly, not saying anything is wrong with it, just asking.

 

[gsryder]

Why do you want to drop the compression slightly, not saying anything is wrong with it, just asking.

When you run a turbo you want to lower the compression depending on how much boost you plan on running. Lower compression helps prevent denotation once the the turbo starts to spool up.

 

[doctorgonzo]

When you run a turbo you want to lower the compression depending on how much boost you plan on running. Lower compression helps prevent denotation once the the turbo starts to spool up.

Oh yeah, forgot about the turbo. Have you been visiting oldskoolsuzuki.info? They have a whole forum devoted to nothing but forced induction.

 

[gsryder]

Been there quit a bit actually, but I like both sites allot of good info. on both.

 

[doctorgonzo]

Been there quit a bit actually, but I like both sites allot of good info. on both.

LOT more users here, and regulars, so much faster answers to questions, but less experience in radical mods.

 

[Steve]

So far I have all the major components - Katana front end, GSRX rear swinger, 1100 engine, Turbo from a 1.8liter Audi A4, ...

You going to change the turbine or compressor housings on the turbo? If not, you won't get much pressure.

The housings on the turbo are sized for that engine and its operating speed, basically meaning airflow. Your engine is only 60% of the size of the Audi, so you will have to run it over 1.5 times faster to get the same results. What's the redline on the Audi? What's the redline on the GS? Yeah, the GS redline might be about 1.5 times the Audi, but the airflow formulas are not linear, they are exponential, so you will likely see just a little boost near redline and not nearly enough below that to make it worth all the effort.

Maybe RapidRay or Blowerbike or one of the other racers/builders can give some specifics on what you might need, I only know the generalities based on trying to fit a wrong turbo on a car.

.

 

[gsryder]

You going to change the turbine or compressor housings on the turbo? If not, you won't get much pressure.

The housings on the turbo are sized for that engine and its operating speed, basically meaning airflow. Your engine is only 60% of the size of the Audi, so you will have to run it over 1.5 times faster to get the same results. What's the redline on the Audi? What's the redline on the GS? Yeah, the GS redline might be about 1.5 times the Audi, but the airflow formulas are not linear, they are exponential, so you will likely see just a little boost near redline and not nearly enough below that to make it worth all the effort.

Maybe RapidRay or Blowerbike or one of the other racers/builders can give some specifics on what you might need, I only know the generalities based on trying to fit a wrong turbo on a car.

.

What you are saying is correct. I wont get massive or crazy power out of that turbo, which I am going from memory I think is a K03. But it will serve it purpose for the time being 1. financially (it was free) and 2. dimensionally it is the same size as a K04 (which is what I would like to have).
So I am basically starting small and using this a learning curve with tuning, fitment, fuel, oil, etc. then I plan to swap out for a bigger turbo if necessary.
Even though the K03 is small I should be able to get around 180hp at the wheel and even if it is a little less or a little more I am basically just doing this for fun.

 

[gsryder]

Here are a few pics of the turbo

Came of a believe a 1994 Audi A4 1.8 liter. I know the guy whos car it was it was a low mileage nice car he drove into a ditch and bent the frame totaling it. So I was able to get the turbo for free.

 

[Grandpa]

Funny story for you Nick and everyone else: your old GK got it's motor torn apart a couple days ago actually. For those that don't know I bought grandpas GK with 130+k miles on it a couple of summers ago. I've since passed it on to my roommie as he gets more joy out of the big bagger than I did. Anyway at 140ish thousand miles now (yes I said 140THOUSAND miles) it finally devoloped enough of a base gasket leak to warrant a tear down and refurb. The head has never been off of this bike. Valves are still in spec and the funniest thing and my point for this story is that the stock cam chain is still in spec by over 50% of it's wear limit. At 140k miles this cam chain givin the current wear rate will last over 280 thousand miles before it would wear to replacement limit. These are tough engines boys. Overbuilt heavily. If you're not increasing HP I don't see a point in a heavy duty anything unless it's just as cheap as the OEM replacement (providing it needs replaced at all)

My goodness, Josh! Thank you for the update on "my" old GS1100GK, the best bike I've ever owned.

I guess it was a matter of time before it would start leaking from the base gasket. What, if anything, are you going to replace on the engine besides new gaskets, o-rings, etc.? Maybe new carb boots?

With the updated suspension, refreshed engine, and the new bearing on the driveshaft, it's a brand new bike!

Nick Diaz
Middletown, MD

 

[Steve]

So I am basically starting small and using this a learning curve with tuning, fitment, fuel, oil, etc. then I plan to swap out for a bigger turbo if necessary.

My opinion? Wrong direction.

Smaller engine needs a smaller turbo.

As I said, it will take one of the racers on the board to get you specific numbers, but I think the turbo is too big.

.

 

[gsryder]

The feed back I got OSS was that it was to small....LOL!
Either way the turbo is a ways off I have a ton of other stuff to do, swing-arm,front end,frame gussets, engine inspection (seals, gaskets and what not), install the 1100 in the 750 frame.

I just took some pics of the first early mock up tonight. I am going to start a build thread here real soon. I am calling it the Cafe/fighter/muscle/soon to be turbo bike...LOL!

 

[Steve]

The feed back I got OSS was that it was to small....LOL!

Please pardon my ignorance, but I don't speak "text".

What is OSS? :-k

Yeah, I have seen "LOL" enough to know what that is, but it is my humble opinion that too many "texting" "words" are finding their way into the real world where full keyboard exist.

About the turbo ... are you sure you heard correctly? Maybe it was said that the bike was too small? :-\\\

.

 

[gsryder]

Sorry man I thought most of the people on here knew what OSS (OldSchoolSuzuki.com) was. Here is the thread I posted over there asking about the turbo in question. I agree it may not be the best turbo for the application but it definitely was the best turbo for the price. Free

Here is the link
http://forum.oldskoolsuzuki.info/cgi-bin/Yabb/YaBB.pl?num=1255823170

 

[Steve]

Sorry man I thought most of the people on here knew what OSS (OldSchoolSuzuki.com) was. Here is the thread I posted over there asking about the turbo in question. I agree it may not be the best turbo for the application but it definitely was the best turbo for the price. Free

Here is the link
http://forum.oldskoolsuzuki.info/cgi-bin/Yabb/YaBB.pl?num=1255823170

Thanks for the clarification.

I don't get to some of the other boards often. I have heard of the OSS site, but there was a word missing from your post that might have led me there.
If you had said "... the feed back I got from OSS ...", I might have guessed, but without the "from", I was totally lost.

Good luck with the turbo, but until you make sure that it will, indeed, work with the displacement of your bike, I think it would be an exercise in futility, not creativity. My guess is that your free turbo might not make any boost at all until the engine is spinning up in the 7,000 range, and then might only make a couple pounds. Those couple pounds of boost will only barely make up for the reduced compression ratio and certainly won't put it up in the 180hp range you are hoping for. Then you have to factor in all the weight you will be carrying with virtually no power increase and the need to change your carb jetting (again) when you end up getting a proper turbo, as your jetting will have to change with the additional air flow at higher boost.

Good luck with your project (I saw your pics in your build thread), I just wanted to try to give you a little heads-up on the turbo selection. It's also possible that I am the one that's due for an eye-opening here, too. I have never tried to adapt a turbo from two engines that were so different, but they might be different enough to compensate. :-k

.

 

[gsryder]

No problem man, I appreciate you constructive opinion. I still have allot of research and learning to do myself. Either way its gonna be interesting!!

 

[koolaid_kid]

Not sure how turbo sizing works on a bike, but for a car if the turbo is too small, it spins up quickly and then is done. It will also tend to glow red at high rpms. If it is too large, it will have lots of lag and not perform as well as expected. Compared to my GT-67, that one is tiny.
Going strictly by displacement, I would expect the turbo from a 1.8 liter engine to be too large for a 1.0 or 1.1 liter engine. However, there are many factors in sizing a turbo; housing style, impeller shape, valve lift and overlap, overall flow characteristics (carbs vs. EFI, head shapes, exhaust flow), rpm range, etc.
Once you get the mounting flange in place and everything working, it is not that difficult to swap turbos out if you need a different one. Also, it appears to use an external wastegate, so you might want to see the Audi guy to see if it is still around. Not sure if a BOV is needed for bikes; for cars autos don't need one but sticks do.
I would expect those that turbo bikes to have the knowledge, so it sounds like you are trying the correct web locations.

 

[Guest]

You find a LOT of ebay resellers selling APE stuff at above the price you could get if you just bought it from APE.

You noticed that. Why so many people think stuff is cheaper if they get it off of e-bay is beyond me.

 

[doctorgonzo]

You noticed that. Why so many people think stuff is cheaper if they get it off of e-bay is beyond me.

You guys did an awesome job on my machine work, and am very satisfied with the whole experience. I'm an APE booster. You'll have another couple sizeable orders from me in the near future.