GSXR "DOT" head on my GS1100

[slayer61]

So over the weekend I dressed the weld on the head using a half round file. It'll work fine for this situation

And I faffed around with AN lines and oil coolers

It's so crazy... :smiley_simmons: these parts were meant to go together!

 

[slayer61]

Parts have arrived from Japan. Thanks Pops!

I also got the cylinder block removed to replace the base gasket & measure up ring gap. The pistons look to be in great shape.

 

[GregT]

I see the cams you've got go in on 103/105 LC's. That'll work fine. My 104/104 gives a slightly wider power band but uinless you dyno it you'll never notice.

 

[slayer61]

Thanks for that Greg. I have seen numbers all over the place with regards to LSA for this motor. I asked on another site where this swap has been done before and was advised as wide as 110 degrees. I think part of the dilemma is because of the slingshot head, a high revving, short stroke motor, combined with a giant slug of a bottom end that will never rev as high as the slingshot 750.

On a more somber note, I pulled one of the compression rings from the no. 1 cylinder to measure the end gap...... and I'm right at the end of the acceptable range.

Now I need to decide how much more money I want to spend on this project.

Speed costs. How fast do you want to go?

 

[GregT]

I was building the 750's with that head for both roadracing bikes and speedway TQ's. The TQ's are fairly heavy vs a bike and single gear on a 1/4 mile oval. You soon learned what worked.
When the GSXR 750's came out most tuners thought the very wide LC's of the aircooled 16V engines were the way to go - 110/112 for a full house 1150. Wasn't till Yoshimura and others actually started serious dyno time that it was realised GSXR's were different - even though the heads are based on the same patent.

 

[slayer61]

Long time, no update. Still waiting for credit cards to cool down a little bit.

1). The buggy is "finished" for the season. More to come next year.

​



2). My wife has a new bathroom.

3). I have been in contact with APE regarding piston kits and machine work of same. If they provide the piston kits, boring & honing is only like $150 for an air cooled 4 cylinder! :applouse:

 

[93Bandit]

What's a DOT head? Sorry, I'm a noob..

 

[slayer61]

What's a DOT head? Sorry, I'm a noob..

The DOT head came from the 88-89 "slingshot" GSXR750 short stroke motors. Called the "DOT" head because of the dime sized casting on the sides of the head. The DOT!



Pic shamelessly borrowed from the interwebz.

The head uses the same bolt spacing as the GS, has a smaller chamber, larger valves and a "semi-down draft" intake tract. As such, I'm (fingers crossed) hoping to make 20-25 more horsepower just bolting on factory parts.

 

[93Bandit]

Ah, OK thanks for the explanation! I was thinking DOT had something to do with Department of Transportation but I couldn't figure the connection. Cleary over thinking this one haha.

In other news, a GSXR750 would be a hoot 'n' a half

 

[Blower]

Interesting project!

I will do slightly similar modification, but with modified Bandit 1200 cylinder block, extra oil pump for head cooling and oil drain pipes from cylinder head to the engine block.
Engine bottom is from 1984 GS1150. Most difficult thing will be extra oil pump, but I have a idea how to install it in the oil sump.

 

[slayer61]

Long time, no update. Still waiting for credit cards to cool down a little bit.

1). The buggy is "finished" for the season. More to come next year.

​



2). My wife has a new bathroom.

3). I have been in contact with APE regarding piston kits and machine work of same. If they provide the piston kits, boring & honing is only like $150 for an air cooled 4 cylinder! :applouse:

And APE tells me that the 1168 kits from Wiseco AND JE are out of stock with no known due date!

 

[slayer61]

Interesting project!

I will do slightly similar modification, but with modified Bandit 1200 cylinder block, extra oil pump for head cooling and oil drain pipes from cylinder head to the engine block.
Engine bottom is from 1984 GS1150. Most difficult thing will be extra oil pump, but I have a idea how to install it in the oil sump.

I've seen your project on oldskool suzuki and it's OFF THE CHARTS cool. I wish I had your talent!

 

[Blower]

Did you had any issues about the cylinder stud length? I using original GS1150 cylinder studs and all of them are about 10 - 12mm too long.
I made 10 and 12 mm long "washers" from aluminum to fix that problem.

 

[slayer61]

Did you had any issues about the cylinder stud length? I using original GS1150 cylinder studs and all of them are about 10 - 12mm too long.
I made 10 and 12 mm long "washers" from aluminum to fix that problem.

I bought APE cylinder studs and it did take some re-arranging to find their "special place". I will know for sure when I get fresh pistons and the head on for the 15th time! I also have a set of APE open top head nuts that might be helpful. Be safe

 

[Blower]

Did you get your engine ready and running?
I got mine up and running and so far it's been working flawlessly.

 

[slayer61]

I have collected a ton of parts, but no movement on it yet. I'm retiring in less than 3 weeks, and moving to Texas right after. What with doing "honeydews" and getting ready to move... the bike just teases me more & more every day

 

[slayer61]

Please do share some pictures of your finished product! That could be just the inspiration I need to get jump started once I get settled in the new house

 

[Blower]

Extra oil pump for cooling.

 

[Blower]

Top end oiling and cooling pipes & hoses.

 

[Blower]

https://youtube.com/shorts/4wBZAYpH-pw?feature=shared