1200 into a 1000 chopped

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What'd I do? I started with this idea of making a quicker cooler bike based on a guy named Papabear on NGW. He had a 1200 in a 1000 that he picked up after the original owner and creator passed away. I had no clue it could be done or not, but he seemed to like it. Then after I picked up a 1200 motor for $125 I was going to put it in an 1100, but the 1100 had title issues, so I decided to try the 1000. At the same time, Superskypilot had a well documented build going on at Saunders. He showed fairly convincingly that the piston mod had to be done. I followed his lead and used double-faced taped and sandpaper on the intake valves to notch the pistons on the 1200. I went with 77 heads, cams, carbs. The mating with the driveshaft is a piece of cake if you remove the rear cover and use the 1000 output shaft. Mine required a little hammer love to the frame to get the 1200 in. It's easier with an 85-87 motor, no ignition in the back. Mine is an 85. I also chopped my frame ala HOTT on NGW and also put in a monoshock from a Suzuki m109. The tank and ignition are from an 05 Meanstreak. I had an 85 Magna I was parting out so I used its front end and a gl1200 set of triple trees. So my bike is a Suzkawahonda. My seat was from a Valkyrie. I really made a bunch of work for myself. Wiring is a spaghetti nightmare, but it works. I also cut the back part of the frame off the main part and moved it back about 1 1/4" and down at least an inch. Anyways, I love the seat height now. Flat foot both feet and knees flexed, I'm 5'10". I know, I didn't think they could stack crap that high either. I have a fair amount of pics, but I seldom find he time to learn to post.

The bike is a screamer. I rode it three or four hours today and took my first highway trip. It runs straight, no shimmy, no wobble, no weave. I am sure I took it up to 90mph or so today, but my tach is not working nor is the seed sensor, so it's all just a guess still. I do have issues. When I really punch it and let it scream, I think I'm probably doing all of 9 grand when I shift, and that engine is pulling like it wants more. The next gears, it jumps. It just plain grabs and jumps forward. The problem occurs after I get on it and slow it down. It then acts like it's missing. I am afraid it's lean, the plugs are pretty white. I do have a float that sticks once in a while. When I got back from the highway trip I pulled the plugs, all kinda white. I also decided to snug the clamps on the intake runners. Some were pretty loose. Hopefully that was my issue. I have two clamps on each intake runner.

I did the relay for the ignition, and I also did the relay for the regulator since I have a small lithium battery. The lithiums are not supposed to see higher voltages , so I cut into the sense wire from the regulator and had the relay connect the sense wire right from the battery. Before the mod my bike would charge over 15v at times. After, it stays in the 13's all the time. I think that will help battery life.

I like my windshield position. It's far enough back without all the gl 1000 gauges that I am out of the wind at all speeds, but I look over the top of it. I don't like looking through the glare.

Here's how it sits with a pillion I hacked together so the better half could ride today. The pillion is a bit short, good thing she still has a small butt.
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My buddy is going to bring his wire feed tomorrow. Hopefully I can get fenders, an air cleaner and some mufflers on it. I have a bunch of little things to finish, but it sure feels good to ride it.

I'll take any suggestions about the missing after giving her the gas. Probably going to have to play with jets some.
 
I wouldn't adjust anything until you get the mufflers on. Then set the air/fuel mix screws. That should pretty much eliminate any missing or popping on decel. What rack of carbs are you running?
 
77carbs. I did the idle drop and resynched. Still does it. When you think about it, the 77's are designed to feed a 250cc cyl. Now it's feeding 300 ccs. I still have absolutely awesome throttle response off idle. I'm thinking mains should be a fifth or a sixth bigger. I will check my junk pile and see if I have some spares to drill.
 
This project is another one of the reasons that I love CGW :good: :salute: :good:
 
If I recall idle drop goes to lean after highest rpm is attained. I prefer to either stop at highest rpm or go richer by 1/4 turn. I may be wrong but I feel if it's a tad rich at idle it's not going lean at higher rpm's.
 
I am pretty sure the idle mixture adjustment will not make and difference at anything after the transition off the idle circuit. If it is lean at high rpm then bigger main jets are required. :yes:
 
I've always had the understanding with these bikes that all the jets work together to supply fuel at higher rpms. This could be myth brought about by someone coining the phrase "everything affects everything" I don't know but it does seem to make sense that fuel could be getting sucked in through the idle jets at higher rpm, not just idle.
 
I did my plug check after cruising an hour at 65-70. I took it for a spin tonight after tightening intake elbows, still pops on decelerating. Tomorrow, maybe I'll try a different cutoff valve. I don't think the idle drops will affect above a couple thousand rpm. It must be the other two jets after that. I can't remember if this set had the washer under the needle either, been too long to remember. I don't think there is because I couldn't find the extras I had. That will help a little. I am really making this up as I go, so any advice is welcome and appreciated.
 
Made a better air filter for it this morning. It's an open adapted 1200 filter. No change in running. Tried a different cutoff valve, no change. This afternoon, I may toy with timing a bit and first thing tomorrow morning, valve adjust/check. As to timing, i just timed it on the 1200 marks. with the 77 heads and cams, would there be a difference, if so, which way? It gives little poofs at idle and loud back fires on deceleration, even slight deceleration. I'm getting a wire feed to borrow to finish up loose ends welding today.
 
Here's what I PM'd Joe: I had my timing set on the 1200 marks. Looked up today that the 1200 is ten degrees BTDC and the 77 is 5 degreesBTDC. So I put mine approximately half way in between the F and T marks. Seems to run better, less back fires and pops out the exhaust. What do you think? I am thinking it should be timed to the 77 setting because that's where the valves and cams are timed to work.
 
Makes sense to me :yes: I have always preferred to set the final timing by ear or feel. I then use the timing light to find out where that is. I have also had instances of faulty rubber in car harmonic balancers and the marks don't line up but the ear does. :good:
 
Sounds right to me. Might even want to advance it further. If advanced too far it will lock trying to start. If it does that retard timing a few degrees and try again.
 
I picked half way between T and F because the F mark on the 1200 crank would be ten degrees BTDC. Can anyone confirm I'm correct on that? T is TDC of the piston, isn't it?
 
eric from what I can find the timing on 1200 is 5 degrees BTDC.....its the swiss modle that's 10 degrees... I thought I went through this ...so I determined the marks were right ...but my info came from trever white pages and might be suspect some of the info is
 
Eric whenever major changes have been made I like to static time. The first thing I do is establish top dead center. This is when the valves are rocking on number 1. The only way to be 100% sure is to remove the valve cover and physically check this. A lot of times I will just pull no1 plug and bring the piston to the top and if the worst comes to the worst I am 180 degrees out. On any interference engine ( Goldwing) I will not risk the 180 degrees out and will check that the valves are rocking. This way you know that you are starting your adjustments from the correct point. Subaru ea82 engines have TDC on the flywheel and also a timing mark and a belt install mark. It is the only engine I know of that you put one timing belt on and then rotate the engine 180 degrees to put on the remaining timing belt.
 
I do remember that, Joe. I am reading p5 in the gallery tech references gl1200 and it says ten degrees BTDC. It also says intake valve begins to open at ten BTDC. With a waste spark, this could be some of the popping I was hearing at idle. Hard to know what info is reliable these days. I may print out a degree wheel and put it on the cam to see how much it moves from F to T. Ansip's way is safest. Thanks for the input. Hope to get some welding done today and maybe some mufflers on. I through pretty good flames right now at night, and I'll get pulled over sooner or later.
 
Just looking up more info, the 75-77's had 37' full advance from 5' BTDC. The 1200 had 45' from ten' BTDC. So we could benefit from a little more advance at the upper end. Maybe tweak the advance plate a bit. I recall Randakk writing that it didn't take much to break the plate just trying to tweak the spring stops.
 
well I finally found the info you were looking at ...sheesh this gets crazy about all the bad info out there ....so assuming this is right more so than trever white pages.....so again eric were challenged I would hold off on the advance mod till we get our heads around this completely ....ill do some looking at thing today also eric
 

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