Help Find A Cure for Crazcnuk's bike?

[Crazcnuk]

I've seen posts about the coils being weak causing issues similar to this, or that the coils just aren't getting enough power from the system (bad connections, et al).

I had never heard of this, coils either worked or they didn't, but you could get better performance from better coils?!?

[TopCatGr58]

Hey Keith/Crazcnuk,

Weak coils can cause incomplete combustion, which can translate into poor performance and poor mileage.

Chop likes to suggest the High $$ coils, Accel or Dyna, but myself and several others have had great success with the Mikes XS ones, they are also high power...35KV, much more than the stock/OEM of 15KV as I have read on here. The OEM's are 25+ years old, as well as just weak due to their design.

Also, have seen your posts for the past year plus, but wouldn't hurt for you to post in a new thread so as not to continue hijacking this one a synopsis of all that you've done to your machine, what mods if any you have, etc.!

Perhaps a fresh review and new eyes may help provide new avenues to investigate for your loss of power??
T.C.

[Crazcnuk]

Doesn't matter. I've had several other posts, and they just wander off the page.

I had no intention of hijacking this thread, people just replied.

I don't care anymore, the damn thing can rot.

nuff said

[skids]

That is the moderator's job. I appreciate all that TC does. Yeah, 'nuff said.

[TopCatGr58]

Hey there Keith,

Shawn's thread wasn't of any great import anyways , I was merely suggesting a new thread with an appropriate subject line so that it could be found/followed more easily! Yeah, they scroll off the main page, but it doesn't take much to find them and BUMP them back up, etc.!!

None of us like to hear about a fellow Xsive that's down on his bike! I think I remember you saying something about nobody being near to help, but I just checked and you are in Hinton, Alberta, and Ken Talbot is in REVELSTOKE, about 100 miles away!?!? Forgive me Ken for offering your services without first asking you, but I think you would be willing to lend a hand to a fellow Xsive in need of assistance!?

So now Keith, if you don't want to bother with trying to recap what has been done, tried, etc., then I'll shut up and go away, but most of us know that these machines can be made to work right, just sometimes takes different/ new approaches!?

[Geezer]

It's to bad that you're so damn far away or I'd drop in and diagnose it for you. It can't be that bad... I've brought some real beasties back to life... I'm sure there are others here that could help you with it. Sometimes it just takes another person looking at it to catch the problem.

Geezer

[stoked]

I don't know why but these carbs are very sensitive to float height. And at least for me fine tuing the height is not easy. I started getting bad mileage and poorer perfomance with rich looking plugs so I started trying to figure it out. I actually thought about leaving it rich and getting smaller jets but I finally seemed to get them all lined up and my gas mileage and performance responded significantly from 30mpg up to 34. Then I think I figured what may have caused to problem. I recently drop the front end way down sliding the tubes up. I slid those succers up a good 5 inches. I may be crazy but I think altering the angle the motor was at that much may have messed with the fuel level that much. So you never know, doing things like adding and removing large items like vetters and what not could have an impact on fuel delivery.

I think the coils from mikexs are a great ider also though. I'm thinking I'm gonna get a pair of those with some of their shocks pretty soon.

[Ken Talbot]

Originally posted by TopCatGr58
Ken Talbot is in REVELSTOKE, about 100 miles away!?!?

Actually, TC, Jasper and Revelstoke are about 530 km apart, approximately 7 hours drive one way. I would be more than willing to help Keith, as I have done with a number of other XSives from within a 3 to 5 hour radius from here. The only thing getting in the way is the logistics.

[Bigleo]

Sounds like your problem could be a combination of coils and carbs. A weak spark can show up as poor top end performance in high gear, almost like a rev limiter.

The carbs!!! Like you, I finally got fed up with the carbs on mine. The reasons were many. In my experience of 8 years of pissing around with these carbs:
1) the rubber 'o' ring around the inlet valve seat is a poor design, prone to leakage.
2) the plastic floats on the 1980s, after 28 years of service are likely gas soaked and don't float all that well, a common problem with similar GM Quadrajet carbs. So setting float levels precisely is next to impossible.
3) the needle jet emulsion tubes are are likely worn, leading to running to rich in the midrange, and new ones are not easily found.
4) the entire midrange power and also the midrange fuel mixture is at the mercy of the large slide spring. After 30 years these springs have probably weakened, and probably not evenly for each carb. So synchronizing the carbs at idle is likely an exercise in futility. I bet at midrange power settings the slides are not even close to each other.
I believe that all of the above issues exist to some degree in most of the XS1100 carbs. These issues would manifest as running rich in the low speed zone up to the 3/4 throttle range, with the resultant hard starting when hot, poor gas mileage, and stumbling and general crappy running until you hit about 5000 rpm.
If you read most of the posts on this site with regards to carb complaints, I have found that they are mostly about fuel leakage and running too rich.
This is why I finally gave up and sprung for the Keihin CR33 carbs from Sudco. They are a bolt on proposition. The big performance difference, the way smoother running, instant hot starting, and the large gas mileage increase, make my old XS1100 seem like a brand new bike. Would never dream of going back to the old carbs.
If you are ever in the Vancouver BC area, give me a call, you can check out the installation and test ride it.
best of luck
Leo

[egsols]

For what it's worth

Craz,

Is your head toast? (the one on the bike) I recall you saying you may have a bent valve. Also, is the head on the 81 motor an 81?

You also said you were burning a litre of oil every 120 miles. That in itself can't be good and no tuning is gonna help. Your compression is 120-125 across the board which, based on my calcs for your elevation (3500 ft) would be 137-144 at sea level. I tested mine, warm engine, throttle wide open, results 160, 160, 156, 168. I'm at 700' above sea level.

Normal is supposed to be around 142, so your compression doesn't sound bad, but have you done any tests to see if it your rings are worn, or if your valves are not sealing?

I think you also said you were running 120 mains with straight thru 4 into 2's and stock air box. I'm wondering if you need to jet down based on elevation. 110's or maybe even one smaller.

I understand your frustration, but that oil thing concerns me.

My two cents.

[Shuriken]

Originally posted by Crazcnuk
My XS gets out accellerated by Royal Star Tour Deluxes and Harley electra glyde UC's.

It tops out about the same speed as a Virago 750 and gets the same fuel mileage as a decent pickup truck.


Ergo it's rotting in the driveway...

I've been frustrated with a couple of XSs that I've owned after discovering who could out run me. Some XSives here have some really fast bikes. The XSs I have had are always a bit beat up when I get them - that plus 6k feet elevation. Put those things together plus some misadjusted carbs and the XS feels pretty slow.

Would be nice to find an XS in a crate, brand new. Break it in and see how it should have felt from the factory.

As it is now, I've been riding an 85 VMax around. It too is/was beat up, but it is still very fast, especially in that 5k-9k roll-on.... I can't help but to think that a perfectly tuned XS with low miles would also pull like mad hell.

[switz1]

Keihin CR33 carbs from Sudco

Had me pumped till I seen the $800.00 price tag.VERY informative post BIGLEO, well said.

[Bigleo]

Hi Switz1,
I know its not a big difference in price, but I think you were looking at the 36mm CRs. The 33mm ones are $698.
The way I looked at it was: OK I can rebuild my old carbs, which I did 8 years ago. This invoves buying new floats, rebuild kits, butterfly seals, new jets for the ones that would inevitably be ruined on dissassembly, a diaphragm or two, etc etc etc, I figured I would easily be up around $300 to $400. And I would still have a 30 year old technology carb that still would not work all that great. So I decided well, for $300 to $400 more, I get brand new carbs with no issues. After the experience with the new carbs, I have to say, I will never run CV type carbs again on any of my bikes.
Leo

[81xsproject]

I think you also said you were running 120 mains with straight thru 4 into 2's and stock air box. I'm wondering if you need to jet down based on elevation.

I agree. I live at sea level, have pods, and a 4-1 and 117.5 are more than enough to keep mine on the rich side. If you're at elevation, I would suggest more along the lines of 112.5's or 115's.

[LoHo]

Crazy, I did the whole litany of repairs for crappy mpg and low/slow power...then I did the vacuum advance wire repair and it all went away...