I'm getting bored

[prometheus578]

"Keep us posted, Poprock."

Be inventive in your endevour:
We're always interested in learning new ways to accomplish difficult tasks, as well as hearing what "choice words" you invented along the way. (in order to expand our knowlege of "salty" mechanic's verbs)

[Pat Kelly]

I went to pick-up the cylinders from the machine shop and I discovered a broken fin . It's not bad, the top left rear fin corner. It won't affect anything but it will cause me to crash. I'll know it's there and I'll keep looking at it because it will be bugging me. So, wife was with me and said "go take to ones off the bike and have that one bored". This leaves me with a few options. If I did that I would then have an XStra set of cylinders (with a broken fin) that have been bored for a 1196 kit. Now, they can't sit around going to waste so I would have to get another 1196 kit and put it in my E . The E dosen't need it so I decided to have Joe (owner of the machine shop) weld on a piece to fill-in the broken fin. So the cylinders won't be ready till next week.

So today I replaced the driveshaft boot. Not too bad a project. Unbolt the driveshaft at the U-joint (front). Have someone hold the rear brake so that you can loosen the 4 bolts. Then I removed the rear wheel and final drive.This allowed the driveshaft to move to the back giving about 1/2" to work the old boot out and the new one in.
That done I started disassembling for the big bore. I disconnected the negative battery cable. Then I removed the carbs and airbox. While removing these I found a bolt holding one of the carb boots missing (a lean cylinder?). I removed the sparkplug wires and the horn wires and moved them outof the way. Then I unscrewed the ballast resistor and moved it out of the way. Then I removed the horns and set them aside. This gave me room to remove the valve cover.


(sorry for the blurry photo, I'll do better)

The valve cover was looking yucky



So I repainted it



Time to fix dinner for the kids. Will do more work tonight.

[Pat Kelly]

I just won two SuperTrapp mufflers off Ebay so I will be doing my 4 into 1 into 2 exhaust setup after breaking-in the engine.

[Wildkat]

Shiny!!

Looks REALLY nice!
(Paint and polish are our friends...)

I'm kind of interested in the 4 into 1 into 2 set up... Keep us posted on how that works for you. I have the same set up on the FJ. Just thought it was a PITA that I had to drop the exhaust to change the oil... Never thought about it until this post (not being the mechanic here) but it has now raised a few questions... I'm curious to see if it will make it run more efficiently... Seems that it would...

How large is the collector on the set you bought?

[Pat Kelly]

The collector is 2 1/4". The muffler inlet(s) is 1 7/8" (x2 = 3 3/4" area). One thing I don't like about the mufflers (which may change when I see them) is they are 3" outlet as opposed to the standard 4". HERE is what they look like. I'll still need to get the diffuser discs and endcaps. They will give me 'tunability' for sound and backpressure. The system being 'neched-down' just after the collector might create enough back-pressure.

I was talking today with the shop that bored the cylinders (and is repairing the broken fin) and he said a "Y" pipe would be easy to weld up.

When I'm ready to have the 'Y' made I'll remove the single pipe/muffler and mount the two mufflers. It should take two 1 7/8" pipes with a 45 degree bend that will come together at the 2 1/4" collector.

Once it is all done I'll send it out to be ceramic coated (gloss black of course) by Jet-Hot coating. Thanks for the link to them DragXS.

I'm trying to keep it looking as stock as possible. With the XSecption of the handlebars.

[Poprock]

Taking engine down

Engine update: got the jugs off Kong today, no problem. Maximan has this wonderful 2.5# deadblow hammer that did the trick. Weird thing is, #2 cyl. was leaking down to 12.5 psi with air blowing out the exhaust valve. Disassembled, everything looks fine. Haven't tested or miked anything yet, just got it apart. Got a couple of mechanical engineer/bikers to consult with for the put-together phase.

[Czekus21]

Weird thing is, #2 cyl. was leaking down to 12.5 psi with air blowing out the exhaust valve. Disassembled, everything looks fine.

Sounds like an exaust valve isn't doing it's job correctlly.

[Pat Kelly]

It must be something in the air

I had my cylinder head upside-down and filled the combustion chambers with carb cleaner to help loosen the carbon build-up. #2 was particularly bad. It's the one that had the carb boot bolt missing. #2 drained empty of the carb cleaner after one day, out the exhaust port. Hopefully is is just carbon build-up on the valve/seat and cleans up ok. I worked on the carbon a bit tonite with a nylon brush in my dremmel, I don't want to use a wire brush on the aluminum.
Got the jugs back. Now to paint them and put them back on the engine. Once they are on I will make a jig to 'degree' the timing marks. Photos to follow.
The mufflers arrived. They're not XSactly what I was hoping but they should work with a little modification. The mounting brackets are in the wrong spot, will have to cut them off and relocate (hate doing that to brand new parts). They came with baffles but no discs. Looking at the baffles, I see no bolt holes for discs so I have some thinking to do on that. Looking at the Super Trapp website, they show different tips for the mufflers (cone, slash, fishtail) so I may have to make something to get the desired back pressure. Just necking-down from the 2 1/4" collector to the two 1 7/8" muffler inlets should help. I don't want the exhaust loud. I don't believe in "loud pipes save lives". If that were true then my insurance would be lower if I ran straight pipes. I do beleive that "loud pipes annoy the people next to and behind you and they may run you over just to get some peace and quiet" . Beside and behind me they can already see me (pulling away ).
The important part is putting the Wiseco Performance Piston decal on my bike. That will make it much faster.

[Pat Kelly]

I used my drill press to remove my valve keepers



I cut a piece of 3/4" PVC like TC did and used it to push down the valve spring and remove the keepers. A shop towel balled-up and placed under the valve held it in place as the spring was compresed





There are valve keepers on the end of the blurry magnet





and the valves came out

[John]

Very Clever

You make it look so easy.

[Pat Kelly]

Of course comming apart is easy. Going back together is never as smooth, we'll see.
Got all the ring ends gapped at .011-.012" for their respective bores. The cylinder is back on and waiting for the work on the head to get done.
Of course I get home Friday morning and SHE has a tractor in the backyard grading my hills. Now I also have to lay paving stones in a 10' x10' square next to the garage and move the shed over there.
Daughter (6 yo) starts Tball Mon afternoon and son #3 (8yo) has coach-pitch baseball on Tue afternoon.

If I loosen or tighten at least one bolt each day eventually the bike will get done.

[Pat Kelly]

Got the ports matched to the intake boots. When bolted on the bore from the carb boots are slightly offset from the intake ports. Shave a little off one side of the boot and a little off the intake port and there's no longer a lip in the intake tract. Had to number the carb boots so they go to the matched cylinder.
Got the head on and the cams in. Following the manual I checked the cam timing and it was off one tooth on the exhaust. I corrected that and I HOPE nothing got bent. Too bad it all has to be back together to find out.
Now to double check the valve clearance, clean the carbs, put another steel disc in the clutch (unless it needs new frictions) and break it in. I may wait on the clutch until the engine is broke-in. I wanna ride it!

[John]

Have you thought about the jetting in the carbs? If you have aftermarket filter and pipes, you may want to increase the mains by at least one size. I had to when I did my big bore.

[Pat Kelly]

After the break-in is done I'll look into fine-tuning my jetting.
I'll be making the 4 into1 into 2 exhaust with the SuperTrapp mufflers (tunable) so things can get complicated.
Are there any tuning guru's out there that can give me guidelines for achieving the optimal back-pressure? (off to search the 'net' for info).

[Pat Kelly]

I did a "Google" search 'exhaust back pressure' and found several informative articles.

Basiclly what is sought after is a good, continous flow. You don't want the exhaust gasses to cool in the exhaust system as cooler gas becomes more dense and slows the flow. This can happen with a too large exhaust pipe.

So, since I'm not after a particularly loud bike I think my set-up will work well for me. A tuned 4 into 1 header with 1.5" headpipes (total of 6" area) into a 2.25" collector. A 'Y' pipe that will go from 2.25" to two 1.875 muffler inlets (equivilent to 3.75" area) and 9 discs in each muffler. These SuperTrapps will use two different methods for sound deadening, absorbtion (the fiberglass packing) and redirection (the exhaust flow routed through the discs). These are an internal disc type of muffler so as the flow exits the discs it is still contained in the muffler body before exiting the outlet. This set-up should create a venturi effect to maintain a good flow with the fast-moving, hottest gas pumped out the 6", necked-down (the venturi) to the 2.25" (to maintain exhaust gas velocity), then out the 3.75" high-flowing mufflers.

So all I need to do is monitor the heat of the exhaust system and add or subtract discs to get an even temperature throughout the system. There's room for about 30 discs in each muffler. These mufflers take the 3" discs instead of the usual 4".

One article talked about ceramic coating (what I want to do to mine). The ceramic coating (inside and outside of the header) helps contain the exhaust temperature and smooths the inner header to promote better exhaust flow.

Another article discussed exhaust pulses and exhaust scavaging, a topic brought-up on this forum occasionally in referance to stock 4 into 2 with cross-over, the Jardine 'spagetti pipes', 4 into 2 no cross-over, and 4 into 1.

My set-up will still be essentially a 4 into 1, just with 2 mufflers instead of the 1. I'm only doing it for astetics, the bike just looks naked on the left side and the muffler that is on the right looks too long and comes back too far. I'm trying to get back to the OEM Midnight Special look exhaust-wise (of course I just can't put the OEM exhaust back on ).

So to answer my question on back-pressure, there is no optimal pressure. You tune it for the engine RPM you want the most power. I tend to run the bike mostly 3 to 5,000 RPM with (frequent) occasional bursts to redline.