GS Big Block

[rapidray]

Now I don't know what to believe?
I'll keep reading.

If you are referring to going 1400, that is with an aftermarket block. The stock 1150 blocks I only go to a max of 1327 & 1260 on the 1100 blocks. My # is 714--356-7845 if you ever have questions. Ray.

[c&c]

If you are referring to going 1400, that is with an aftermarket block. The stock 1150 blocks I only go to a max of 1327 & 1260 on the 1100 blocks. My # is 714--356-7845 if you ever have questions. Ray.

Guys! I wish I had your combined knowledge!

[rapidray]

They REALLY aren't hard to build. You gain experience with every one you do. I was luckier than most having grown up in my Dad's race shop. Make your decision what size you want to build & I will be happy to help you with a specific list of what parts you will need & how to make it live at the power level you decide you want. Ray.

[c&c]

They REALLY aren't hard to build. You gain experience with every one you do. I was luckier than most having grown up in my Dad's race shop. Make your decision what size you want to build & I will be happy to help you with a specific list of what parts you will need & how to make it live at the power level you decide you want. Ray.

Super!

Ill be posting soon. Winter is coming.

[yoshisakan]

I'm picking up my new bandit 1200 engine tonight! First step is a tear down to replace the gaskets and do head work. Are 1mm oversized valves worth the additional ~$800? I'm going to get it ported, polished, cammed and otherwise built before I install it on the bike.

Also, anyone know the weight difference between the 16v 1100 and the bandit 1200?

[rapidray]

That head will use 30mm intakes & 26mm exhaust valves with just a valve job. Worth the money! Ray.

[yoshisakan]

That head will use 30mm intakes & 26mm exhaust valves with just a valve job. Worth the money! Ray.

Ray, I meant that it will cost me another $800 to use 1mm bigger valves. Is that worth it? I don't own a flow bench (yet) and don't know the cfm that the stock head flows vs bigger valves, nor can I really translate that to HP gains. I need some math and numbers haha

I did pick the engine up yesterday though. It's the cleanest 29k engine i've ever seen. Did a leak down test and the valves need lapped a bit, but the piston rings are solid. It held 95 psi with no air leaking into the crank case. Best $700 spent ever.

[rapidray]

The valves cost the same amount, no matter what size. You will have to do a valve job regardless so it will be better to go with the bigger valves so they are already in there later when you decide to go bigger pistons & cams. Yes, it is worth the money. To give you an idea, the valves are 400, valve job 250, seals 45, springs 110, porting 400, & disassemble, clean, reassemble setting spring pressures 100, for a total of 1305. That would be a head that would support 180 hp EASILY & work on a motor from stock to as big as 1400cc. All new parts & a very streetable or raceable head. That is just to give you an idea what you are looking at to have one built. Be careful if you are dealing with an automotive machine shop as bike heads are a little different than car heads. A RACING shop automotive machinist will know how to do them right if they are a GOOD shop. Ray.

[yoshisakan]

The valves cost the same amount, no matter what size. You will have to do a valve job regardless so it will be better to go with the bigger valves so they are already in there later when you decide to go bigger pistons & cams. Yes, it is worth the money. To give you an idea, the valves are 400, valve job 250, seals 45, springs 110, porting 400, & disassemble, clean, reassemble setting spring pressures 100, for a total of 1195. That would be a head that would support 180 hp EASILY & work on a motor from stock to as big as 1400cc. All new parts & a very streetable or raceable head. That is just to give you an idea what you are looking at to have one built. Be careful if you are dealing with an automotive machine shop as bike heads are a little different than car heads. A RACING shop automotive machinist will know how to do them right if they are a GOOD shop. Ray.

Yeah, if I have the head off, i'm going to replace the head and base gaskets with metal ones if I can find them, definitely ordering cams too. I feel like the piston rings are in great shape, so i'll run with them until they cause a problem or until I throw a street shot of nitrous at it, haha. Do you know of any good shops near Cleveland?

[blowerbike]

i believe the gaskets are steel shim type already.
not sure if motorhead(dennis) is still doing his thing in cleveland.

[rapidray]

Terry is correct, the stock gaskets are steel shim. Ray.

[yoshisakan]

There's really a lot of great information in this thread. Thanks to everyone for contributing.

As far as carbs, what's the best starting point as far as matching them to your engine's cfm? In a perfect world, I could flow bench an assembled motor and match the correct fuel to it. In my case, my 1200 motor does not have carbs, so I'll either be looking for some used stock carbs and jet them, or maybe spend a little more for 38mm or 40mm mikuni flatslides. I'm not sure of the power difference between the two. Regardless, what's a good starting point as far as finding the correct jet sizes?

[rapidray]

Depending on what your plans are for the motor will determine what size carbs you put on it. If you leave it stock, the 36 RSs or the FCR 37s will work great. If you are porting & camming it, the 38 RSs or 39 FCRs. If you are doing all of the headwork & cams plus going 1216 or bigger, the 40 RSs or 41 FCRs will work. Carb size depends on what you do to the engine & head. Ray.