Single carb mod for skorpion

[hb7]

"No towning such manifold anymore...." i think he means that this setup is not street friendly.
The long intake runners may be very good for flatout on the track but not friendly on the street.
The intake and exhaust tuning on singles is a complicated engineering exercise.

What everybody wants to know, what mods work on the street or for that matter what are the most effective mods
that shade tree mechanics can execute successfully....(my apologies to shade trees)

[Bill Jurgenson]

dunno
I deluded mysrlf into thinking I was writing English.
I specifically wrote (and more than once) that the Bikeworx header is not for racing. I also wrote that the longer headers are better for midrange. The Bikeworx manifold with TM42 is great on the street.
I also wrote that for serious racing virtually all run dual flatslides, for the most part on headers somewhere around 2" long. For really really serious HP, you have to weld up the intake ports and reposition them to be the same size, serving the middle valve equally. When this is the case, the header unit is bolted directly to the head.

I'm getting very, very tired of repeating myself cause others don't (can't ? aren't able? are too lazy to bother?) to read what's there and/or search the archives.

[Norton19s626]

Hello All,
I've been reading this single carb forum and would like to ask this question: Is there some kind soul who will send me the dimensions for the Bikeworx Skorpion inlet manifold so's I can fit a Raptor 660 carb conversion? I have some fabricating skills and can make my own manifold.
I tried contacting Galen Miller at Bikeworx and was informed that he no longer had any MuZ carb kits and wasn't going to make any more, I could try Dale Walker over at Holeshot but have the feeling my luck will be similar.
I noted the comment about old British thumpers and their idle speed, typically they had about 7.5:1 compression and actual flywheels, the ones in my Norton 19s are 8 inches across and weigh over 25 pounds, it has more low down torque than any modern single, but even a modern 180cc Honda scooter will dust it off at the stoplight drags. I didn't buy it for the speed, that's why I have my Skorpion and a hot rodded SR 500 Yamaha.
Regards,
Albert

[basser23]

I am sure Dale wont have any anymore....hasnt for several years..
by the way,the raptor carbs will not fit under the Skorp tank as they interfere with the petcock
morbidelli17 did a custom Grizzly/FCR41 manifold on his race bike using a spacer plate cnc'd for the different bolt pattern

[Norton19s626]

Hi,
I didn't think that either Dale Walker or Galen Miller had any Skorpion single carb kits lying about for me to buy. I would like to get the dimensions for the single carb intake manifold so I can make my own, the photo posted by Mr. Jurgenson gives me an idea of its appearance, but not its dimensions.
Regards,
Albert

[Bill Jurgenson]

the two pipes fit into the rubber mounts on the cylinder head as they are; that is simple enuf.
The carb is mounted in a Mikuni bolt-on (fits a Harley) mountso buy that first and then miter the tubing to match up.
The two first miters must also bend down so that the manifold is horizontal, otherwise the big carb will not fit under the Skorpion tank.

[abdoujarapov]

I can remember a time when everybody wanted twin carbs. Having read this whole thread I think I'll just stick with the gay hairdresser as suggested earlier on. He could well turn out to be an old friend.

[edfmaniac]

I was reading one of Bill's earlier posts in this thread and came across the Mikuni BST 40, Grizzly manifold reference. Is this a bolt on mod for the Skorpion, or would it hit the tank, and what kind of gain should I expect over the stock twin carb set up with 11:1 CR, Stage 1 Hotcam and 686 bore?

Thanks,
Victor

[edfmaniac]

If the Grizzly manifold isn't a bolt in mod because it's too short, wouldn't it be easy to make a coupler to go between the carb and oem intake manifold. It seems that would be much easier than fabricating the whole manifold from scratch. Just throwing the idea out there.

Victor

[OLDMTNCARVER]

Several years ago I talked to Dale as he's in the area. He stated very plainly that he had no interest with MZs, carbs or exhaust. I can't say that this has not changed but since MZ, (the old company owners) "dumped on the purchasers of their product line" leaving this country I'd bet against it.

I called Galen asking about carb kits and manifolds, some time ago and he told me that the kits he had where gone...

OMC

[Bill Jurgenson]

http://www.mzriders.com/posting.php?mode=reply&f=3&t=5187#pr26677

1) the Grizzly header does not fit. Neither of them.
2) one can make an adapter spacer; I have and have at one time or other uploaded pics; it is not a good alternative.
3) I bought all 5 of Galen's manifolds for HWE Motorsport in Karlsruhe. They are not for sale.
4) Except for Galen's complete kit, none of this is bolt on.
5) I cannot see any gain by using a BST40 instead of the stock Teikei, on the contrary. Why would anyone want to replace a slider carb for a single CV carb? Isn't the response sluggish enuf already?
6) the best and cheapest at the bottom line carb conversion for the stock or mildly tuned Skorpion is the Mikuni TM34-B65. Galen's kit was very good, but it was NOT cheap and it can no longer be had.
7) all of this and a lot more has been posted with pics and links umpteen times.

[Old Dog]

Hey Bill, you're getting cranky my old cobber, we all post and repost the same info - mind yours are alway very comprehensive.

Speak soon

[edfmaniac]

http://www.mzriders.com/posting.php?mode=reply&f=3&t=5187#pr26677

1) the Grizzly header does not fit. Neither of them.
2) one can make an adapter spacer; I have and have at one time or other uploaded pics; it is not a good alternative.
3) I bought all 5 of Galen's manifolds for HWE Motorsport in Karlsruhe. They are not for sale.
4) Except for Galen's complete kit, none of this is bolt on.
5) I cannot see any gain by using a BST40 instead of the stock Teikei, on the contrary. Why would anyone want to replace a slider carb for a single CV carb? Isn't the response sluggish enuf already?
6) the best and cheapest at the bottom line carb conversion for the stock or mildly tuned Skorpion is the Mikuni TM34-B65. Galen's kit was very good, but it was NOT cheap and it can no longer be had.
7) all of this and a lot more has been posted with pics and links umpteen times.

Yes, you are very generous with your time even though you sometimes come across as very impatient. We all appreciate your expertise but you should realize that finding anything on this site is damn near impossible without investing many hours of reading. Even then, without asking for clairfication, it's sometimes hard to tell what some people are trying to say. Your last response is a perfect example. You state that the Grizzly header does not fit, neither of them, then follow up by stating that you can make an adapter spacer but it's not a good alternative. Are you saying that it doesn't fit the engine or that it doesn't fit the Skorpion application and is it because of tank clearance or different bolt pattern? Why is it not a good alternative? Is it because of the not fitting the engine or is it the flow characteristics after adding the adapter? Answer if you like but I'm just pointing out that we all have different perspectives and understandings about the topic at hand and each is different.

Thanks again for all your time,
Victor

[harold]

Bill gave me some good advice on my single Mikuni mod. The Grizzly manifold has the ports closer together than our head, thus needing an adapter of some kind. On the Baghira, there isn't room for the carb, so I had to cut a frame member and mount the carb around 6" back from the head where the air box used to be. It works and jetting is now simple and available. Niether were true with the stock carbs. If you search on my posts, you will see how I did it, and it won't take that long to find them. It looks like it would be quite a bit simpler on a Scorpion.

[edfmaniac]

Thanks, I found the pictures of your mod. That's pretty much clears it up. It looks like it would be easier to fab a part just like the one in the Bikeworx kit. I can buy and/or make all of the parts with a hacksaw and file and have a friend weld it up.