High Speed/RPM pass now bike runs BAD - What to check?

I was in 2nd gear about 45mph and passed someone (quickly) and was at about 65mph and 9.5k rpm when I got back into the lane and started to slow down (55mph country road) and shift into 3rd.

Before someone tells me I should be shifting in the RED zone anyways this year I have been trying to shift around 8k and riding in lower gears than last year so I "cruise" at 6.5k vs 5.5k.

As soon as I was done passing the bike just didn't feel or sound right. It was louder and sluggish for the remaining 7+ miles to work.

After work, the area around the bike smelled a little like gas. I didn't see any leaks or puddles before or after I started the bike. On the 15 mile ride home it still smelled a little like gas.

The ride home was sluggish and louder than normal. I was a little concerned I would not make it home.

So...

What are some of the first things I should check/do before I even consider riding it again?

I was planning on checking oil level and smelling it for gas as well as check for visual damage and any new leakage.

NOTE: I am overdue for an oil change, have not done my carbs yet or adjusted valve shims. I know I'm rolling the dice and time will run out eventually on me...

What might have gotten jarred loose and/or damaged by my higher-than-normal-rpm and RASH passing maneuver? (I usually don't pass as hastily as I did today - there was a semi truck coming the other way and the guy was doing 10 under and I was on the way to work...)

 

How's the oil levels and the compression? Plugs? Can you see the level through the sight window? I don't suppose your exhaust is lose or something or you blew a hole in your exhaust to make it louder? No valve clearance checks for a wizard? tsk tsk If you're smelling gas follow the fuel from the tank on in, and check the airbox.

If you're lucky and didn't damage something internal it's time to look after those carbs and shims dude!

 

I know I know... Been lazy and wanting to paint a spare cover (still didn't happen) before I install it with a new gasket and donuts (which I have).

 

Wait hold on.

The bike has 21K and you've never checked the valves?

8O

Unless the "blast" of increased vibration shook something loose in the carbs, the first thing you need to do is at least CHECK the valve clearances.

Then do a compression test. Hopefully you didn't just burn a valve, (or hole a piston for that matter.)

 

:O uh oh

 

Lazy "Wizard" maintenance steps in progress.

Oil Change
1. Found my oil filter kit with big and small oring and a spring.
2. Bought some more (motorcycle) oil.
3. Grabbed a 1/2" Breaker Bar and 12mm impact socket and was able to "break" filter cover bolt free w/o any problems (and promptly turned it back a hair). WOOT!!!

Valve Shims and Oil Leak:
1. Ordered the POR-15 brand paint I want to use on the cover and other parts of the bike.
2. NEARLY got all of the stubborn paint off the cover. More paint remover and drill/dremel wire brushed in the corners are probably next.
Note: I already have new donuts and a gasket as well as the valve shim tool.

Front Brakes/Front End:
1. Ordered the caliper piston & seals kits along with most every rubber/gasket parts and clips from the forks all the way up to the handle bars (including air assist gaskets).
Note: I have the SS lines, brake pads, MC rebuild kit and bolts/washers needed for the job. I'll order the tapered head bearing kit if needed.

Working 2nd shift 6 nights a week is not going to leave me alot of time/energy to get my bike redone RIGHT and visually the way I want it. This might be a limited riding season unless work hours change soon, which they probably will (probably 12 shifts instead of forced overtime as plant moves to 24-7 from 24-5 days a week).

 

**TIP**

When you have some original clearcoat that's so baked on even aircraft paint remover bounces off, try a shot of Permatex spray-type gasket remover. The original, politically incorrect nasty stuff; it's even meaner than the aircraft remover.

Now back to the bike: you still don't know if/how you blew it up?

 

No I have not risked another ride. Also I really am tired and lazy before work.

I figured this was a warning to do the basic and major maintenance. Hopefully nothing major broke.

I'll do the oil change first, then test ride around house and go from there.

WORST case I do have a parts bike (unknown compression).

Good tip about paint removal.

 

At least test the compression before running it any more. If you did "drop" a valve, or did some other damage, running it could just hurt it more.

I would diagnose the motor before you fire it up again. You don't need to start it to at least CHECK the valve clearances and test compression.

 

OK. But I did run it 5 min and a few hundred yard before the oil change I'm in the middle of....

 

OK, so when you button it back up from the oil change, check the compression. If you find three good cylinders and one sour one, you don't want to run it any more at all.

If you do get any wacky results, pop the valve cover and check the clearances.

 

OK cool. I have a compression tester.

 

I didn't take to many embarrassing BEFORE pictures, but I actually thought the oil filter cover was painted black. It had so much oil and grime build up on it, I was thinking I wish I had time to repaint it black... EDIT: Valve cover and donuts are seeping. As far as I know the oil filter/drain were not.

I'll may splurge for the spin on filter later this season. If not, I'll grab another normal filter and do another oil change a few weeks after getting it running RIGHT again. This way I'll get more of the old thick and black oil out of the system.

Time and energy permitting I'll check compression Monday or Tuesday morning before work. The valve spacing may have to wait till the weekend and I pick up some feeler gauges. (I thought I had everything purchased over winter).

Click for larger:

 

Update and More Info:

So I had time to do a 5min WARMED engine DRY compression test only. (Ran out of time before work to do wet with oil. I had to remove my lower fairing pieces to barely get to the #1 and #4 spark plugs with the OEM spark plug tool that came with the bike).

In order from 1 to 4:
140 - 145 - 145 - 150 (Jumped instantly to about 125-135 then settled on final readings - Did each one 4 cranks each - Still had 13.02 V left).
Per Yamaha Service manual:
Standard 156 psi; Min 128 psi; Max 171 psi - with Max variance of 14 psi

I haven't had a chance to buy feeler gauges yet and I'll have to totally take off my fairing to remove the cover anyways. (My paint should arrive soon so I can paint the cover while awaiting shims in the mail).

I did crawl around on the ground looking for leaks and any sources of extra noise. Last winter (cold air) I did notice one of my mufflers does "leak" at the joint to the muffer and the connecting pipe from the collector. Now both appear to be leaking. This can hopefully just be fixed with new gaskets? I assume this will affect back pressure and overall performance, but these leaks are not really new or SUDDEN to explain my recent issues.

I DEFINITELY WANT/NEED to redo the carbs (after valve shims measured/replaced). Should I redo my "running" carbs or 1 of the 2 spare racks I have? Or even pull the rack off my parts bike? My plan was always to do one of the spares in case I broke something or wanted/needed to put the "running" carbs back on while re-redo'ing the spare set as needed.

Is there any thing else less obvious I should check? Or is it hard to say/pointless until I do shims and Carbs?

 

I am new to bikes, but thanks to my recent purchase of an xj650 I've learned so so so much.

Any chance you ruptured the rubber in the petcock valve? It would explain the smell of gas and sluggishness from running super rich on carbs 1 and probably 2. Also might explain why one of your plugs looks damned near black while the rest look... decent.

But I don't know, maybe not...

 

OMG Bob, change those plugs! And adjust your exhaust stat!

 

+1.

I suspect he's got sticky floats in addition to the leaky exhaust.

And/or a couple of tight valves; although no damage yet as the compression numbers came out decent.

The high-RPM blast could have split a valve stem seal too (anything's possible) but until we get some new plugs in there and then see what those look like, who's to say?

C'mon, Bob, NGK's are $1.99 at AutoZone.

 

Umm... no, it wouldn't. The petcock feeds fuel to the carbs. The carbs (specifically the floats) control the amount of fuel that goes to the motor.

A problem with the petcock would be completely unrelated; and it's equally unlikely that the petcock diaphragm would rupture from running the motor as designed.

The smell of gas and sluggishness along with running super rich WOULD be consistent with a sticky/stuck float however.

 

I have all intentions of:
Changing Plugs
Valve Shims
Exhaust Leaks - I have some questions below
Carbs
Front Brake system rebuild and both wheel bearings (and head bearings as needed).

Exhaust Questions:
Are the gaskets connecting the Mufflers to the Collector pipes typically reusable? I.E. Could I pull off the gaskets (and Mufflers) from my parts bike and slap them on my (sorta) running bike and expect them to NOT leak?

How hard is it usually to remove the Mufflers and their gaskets?

I know the Header Collar Bolts/Studs can be a bitch, but what about removing the collector assembly? (For future Por-15 painting project).

Compression:
Should I bother with the WET test before I fix the shims/clearances? Do I need to bother with WET after clearances are correct based on my initial dry tests?

FYI: I probably would have been one of those guys that let my XJ sit for 25 years once the carbs and/or valve clearances got fowled. But I was only 9 when my bike was released.

 

Mini Update:
I bought some new spark plugs. (Darn Farm Fleet store seemed to carry every NGK plug size except the ones I needed); along with brush on gasket adhesive for valve cover; also gasket remover spray can, as suggested, to help get off some remaining stubborn paint.

My POR-15 paint arrived today. So I can paint my spare Valve Cover soon and check/replace the valve shims. I didn't get feeler gauges, but I wanted to check Menards and/or Lowes to see if they had METRIC ones in stock.

I also started a new post asking questions about oddities noticed why trying to remove my mufflers (to swap from parts bike or just get new gaskets installed).
http://xjbikes.com/Forums/viewtopic/p=3 ... tml#326516

EDIT: After reading a comment in another post about checking oil after a change (if it goes up after running for a few, probably leaking gas from carbs into oil), I realize I have yet another reason to "DO" my carbs.

Maybe the GAS SMELL (as mentioned in the first post) was some gassy-oil leaking out of my valve cover and heating up, thus I smelled it...

Would the sudden dumping of gas from the carbs be ONE of the causes of my sluggish/loud symptoms?

 

Making some SLOW progress:
* I managed to get the left muffler off.
* Areo Kroil and a few days of sitting allowed me to loosen all 16 header bolts with ease (2 bikes). I also loosened the collector-to-frame bolts on both bikes.
* Fairing removed for the overhaul processes
* Took off saddlebag (easy process) for better access
* Broke loose the Valve Cover bolts - I need to find my allen sockets!
* Gas tank obviously removed for cover access. Hopefully I can seal my replacement tank and install that when done with everything else.
* Received 23/27 OEM parts used to rebuild my front forks, trees, air assist, etc. 4 same # O-Rings are on backorder. I'll probably end up ordering the tapered head bearing from Chacal as well...

I have Metric feeler gauages in hand now. So checking valve clearances and shims will be the next project. I'll probably remove the carbs the same day (time permitting). Even more time permitting I'll yank off both exhaust systems and prep them for bike-to-bike swapping.

My poor bike looks so naked!


Another pile of parts to add to my existing pile of parts waiting to be installed.

 

Hey Bob, did you take a peek up the butt of the pipes? As I read your story of passing the car....what came to mind was, had you been riding a two stroke was losing a baffle but I'm wondering if you blew out one of your mufflers. Without the back pressure, it would have lost it's edge and def would have instantly been louder....just a thought buddy.

The other thought was to isolate where the increase in sound is coming from. Louder exhaust or intake?

jeff

jeff

 

Updates in case anyone is bored enough to keep reading them

Valves:

Clearance Numbers, Original Shims and shims needed to get to high end of tolerance:

Intake Tolerance 0.11~0.15mm
Exhaust Tolerance 0.16~0.20mm

1 Exhaust 14mm - 270 --> 265
1 Intake 14mm - 285

2 Exhaust 17mm - 270
2 Intake 14mm - 290

3 Exhaust 16mm - 270??
(99% sure but very hard to read and forgot to buy a micrometer. It is in spec, so it's not a big deal at this time.)
3 Intake 14mm - 290

4 Exhaust 17mm - 270
4 Intake 10mm - 275 --> 270
That means I can re-use the 1Exhaust shim.

For just ONE shim, it is probably NOT worth it to crack open parts bike and check those shims (it is red RTV siliconed :twisted: ) for a possible swap.

Valves Cover:
I managed to finish POR-15 Silver base coating it. If my back stops hurting after leaning over the bike for so long (8th valve took like 12 tries to get the tool in place), I might paint the black part of the cover.

Carbs:

I bought a gallon can with basket of carb cleaner and 2 spray cans as well.
I eBay ordered SS allen head screws for the external parts of the carb assembly.
I plan on ordering other tools from Chacal for cleaning/syncing/tuning in the next day or 2.
I want to start tearing apart 1 or 2 of my spare carb racks this week. The sooner I get started, the sooner the bike will be running again!! 6-Day work week + additional overtime sucks for getting projects done. :x

Exhast:

I still want to paint the headers/collector black with POR-15 Black Velvet. I haven't decided on the mufflers yet. (Some Secas look good blackened with chrome mufflers).

I think I'm going to try loosening headers from collectors and if I'm real lucky the gaskets will be reusable. Best case I can keep RUNNING headers on bike and swap in Collector+Mufflers from PARTS BIKE as one assembly. This should make it easier to clean and paint the headers/collector and not have to buy new muffler gaskets or try to get them back onto the collector pipes. (NOTE: Buying ALL of the exhaust gaskets at one time is NOT cheap - even for aftermarket one).

Front Brakes:

I NOW have all the PARTS I need to rebuild entire front brake system. (I may need one of those 3 stone honing tools and a grease gun still). However, I want/need to repaint MC and calipers. So other than the time it takes to bleed, that project will be delayed by painting and prepping. But that might wait a little longer. I want the bike RUNNING by mid JULY at the latest. Kinda hard working 2nd shift 6 days a week, but I'm going to try.

Front Forks & Bearings:

I think I have all the parts needed for a thorough rebuild of the Air-Assisted front forks including Progressive springs. I'll be painting the lower forks during the project (or a spare set before hand).

I have front & rear wheel bearing kits waiting to be installed.

I think I'll buy Chacal's tapered Head bearings and swing arm bearings/gaskets when I do the front forks.

Heck I'll check the tires wear and maybe re-balance them at that time as well. I might as well eliminate all wobble sources as possible. (As far as I know the frame is straight...)

 

I just sent off a huge/price Request for Quote to Chacal for several carb cleaning, syncing and tuning tools... I hope I don't die from the final price shock! LOL

 

RE: Painting exhaust pipes. If you really want a finish to LAST on header pipes, don't paint them. I have never seen painted headers stay nice for more than a season, ever.

However, THIS process works, works well and holds up: http://www.jet-hot.com/

Also, remember not to submerge any carburetor that still has the throttle shaft/butterfly in place, lest you damage the throttle shaft seals.

 

If your mufflers are physically off the bike, youcan shake them, or shake the whole exhaust assembly and hear if it rattles, or is everything still tight.

It would also be the way to determine where the loose baffle is.

Do I see Sportster mufflers in your future??

 

I'm going to go with a simple suggestion.....as I've seen this happen more than once.

it is entirely possible that you had a jet shake loose. I wouldn't be surprised if you find it rolling around in the carb bowl.

Dave F

 

My "running" Left muffler is rattling inside.

The "parts" exhaust system is rattling a little. I'll have to figure out where...

I'd probably get those JC whitney slip ons before some Sportster ones, unless i could get them DIRT cheap somewhere...

- - - - -

Tonight I took off my "parts" exhaust system as one piece. I would definetly be hard to reinstall it complete... Maybe doable if all of the joints are loose but connected (to reuse gaskets).

On the parts bike I broke 3/4 bolts and 1/4 on the running bike (1 still unloosened). The bolts are small, rusty, brittle and apparently didn't have enough Kroil for long enough. :x



I'm not sure if the bolts moved any or simply twisted a bit before snapping. I soaked them in kroil before cleaning up for the night. So hopefully they'll be easier to remove when I get to it.

I dug out my SPARE carb racks (from eBay and a former XJ owner/forum member. They are UGLY, dirty and rusty looking. My parts bike's set is cleaner looking than my main carbs. I think I'll try rebuilding that set.

From memory my "running" carbs' #2 idle set screw hole threads are all chewed up and I was unable to move the screw when I first got the bike. So I always knew I'd be replacing parts or the rack. This is why I have so many spare carbs

I'm sure there is stuff wrong with the carbs. I believe the carbs are NOW leaking into the oil. So I'm planning on finally doing everything right

I just bought a bunch of cleaning and tuning tools from chacal. Once I tear into a carb rack I'll buy some replacement parts.

 

Umm, Bob...

Are you talking about those little bolts on the bottoms of the exhaust pipes, or the clamp bolts?

Those little bolts have NOTHING to do with holding the pipes on (and they're not drain plugs either.) They're the EGA ports for doing an EGA carb sync. They don't need to be removed unless you're planning to use an EGA or need to get the collars all the way off.

The only bolts that hold the pipes to the collector are the ones in the clamps.

 

Take a half-dozen 10d Nails to the Grinder and "Taper" opposing sides to a point.
Grease the Nails.
Use them to Widen and Open the Clamps surrounding the Bottom of the Header Pipes.

Apply Penetrating Oil
Remove Nails

Attach 2-Feet of Strong Nylon Line to the Lower Bend on the Header Pipe.
::: Use a Locked Clove Hitch so the Line does not come undone. :::
Loosen the Pipe with Left and Right Blows from a Rubber Mallet.

Affix the Bitter-end of the Line to a Heavy Duty Dent Puller.
••> With assistants steadying the Bike <••
Apply a Left and Right Blow with the Rubber Mallet.
Using the Puller:
Tie the Line to the Puller
Take up Slack
Apply a few sharp Blows to the Pipe straight ahead.

Continue for 45-Minutes to 1-Hour before taking a break.
Upon continuing:
• Send children to stay with relatives.
• Alert neighbors to ignore disturbances.
• Call Police Business-line and give them a heads-up before other calls flood-in.

 

Oh well... I'll replace them if I can them out...

It must have been a LONG day when you did that job... That scares me a little...

- - - - -

I got my donor carb rack off the RED Parts bike. I think I'll just call here Connie for now. Off was not so bad. ON is the hard part I now see...

The Carb-to-Engine boots on Connie seem to have surface cracks. I didn't take them off to see if the go all the way thru the boots.

Anyone tried that On-TV rubber spray sealer to externally repair XJ boots?

I did nab a set of those boots off of eBay and have a set of airbox-to-carb boots from a prior truckload of parts buy. (I haven't checked condition)

I've sealed up Connie's exhaust header holes, carb holes and airbox intake holes with paper towels wrapped in aluminum foil. Then I wrapped the front of the airbox (with the 4 boot holes) with aluminum foil. Then I put the motorcycle cover back on the bike (stored outside - no garage). Hopefully this will keep nesting animals and some bugs out of the bike...

Connie's ??Drain valve screws?? seem a bit chewed up and well used. I soaked most of the external surfaces (and screws obviously) with KROIL. I'll let it sit for a day or 2 before I touch it again. (I have a 12 hour shift today - more money for parts/tools but makes me sleepy).

Like my hole sealers?


These screws are a bit chewed up - #1 (or was it #4) looked the worst...


Look mom I pulled my own carbs! (Little kid voice as I drip gas and oil all over the kitchen floor). :lol:

 

To remove Stuck and Buggered Drain Screws.

Remove Bowl.
Fabricate a Screw Slot using a DREMEL Fine Tipped Cutting Bit affixed to a Flexible Wand Attachment.
Remove the Screw with a Hand Held Impact Tool.

Place a Hammer Handle in the Vice
Angle the Vice and Handle to allow an assistant to hold the Fuel Bowl upon the anchored Hammer Handle so that the Bowl will NOT move when the Stuck Screw is subjected to the Impact Strike.

Hand Held Impact Tool
1/2 -to- 3/8 Adapter
3/8 Bit Holding Socket
Screwdriver Bit -- Shaped at Grinder to fit Drain Hole and Slot.

 

I will give all of that a try if a 4 bowl transplant is un-successful.

I looked at all 4 screw heads again today. Basically all of them are chewed up and probably way over tightened...

I grabbed one of my "loose" racks (one from eBay one from a former member here). The first screw broke loose w/o any problems. I KROIL'ed the remaining 7 screws on the 2 racks along with the bowl screws. I should be able to get one good set of transplanted bowls with the screws being removable/replaceable.

A quick look at my running bike's (VAL) carbs. They are a bit chewed up but not as bad as first rack I tried (Connie's).

I THINK I'm going to BREAK the Connie's rack apart and fully clean and rebuild/replace the rubber bits. I figured a few extra hours of work is better than finding out I needed to replace the seals anyways...

My valve shim and carb cleaning tools should be here today or tomorrow (I hope). If I'm lucky I'll have 1/2 a day to work on my bike on Saturday...

Waking up tired/late and coming home worn out, leaves very little time to get anything done (motorcycle related or not). At least the 6th day overtime is paying for this year's bike maintenance

 

I managed to break loose 3/4 of a "spare rack's" drain screws. I left a puddle of KROIL sitting in the 4th screw area before I came back in for the night.

I tried loosening Connie's screws and the other eBay rack w/o any luck. I'll buy a screw extractor if I have to, but I'm hoping more time with the kroil and my hand held Impact driver will do the trick.

I sent of my carb parts RFQ to chacal. Thank goodness for overtime $$.

Looking at the carb bodies I'm thinking I'll paint them as well (going to paint engine eventually). I think I want the hats, bowls and rails to be black (to contrast the SS allen head screws I ordered) and the carb body and most everything else silver. I'll keep using the POR-15 Silver paint and Engine or Chassis Coat black paints I already have (to match engine and other painting projects).

It has been to cold at night to finish painting my valve cover (the black sections) and I've been to tired in the morning (or waking late) to start the project before work.

 

DO NOT PAINT YOUR CARBS. They can be cleaned up very nicely.

Get the hats, and bowls (if you insist) powder-coated, leave everything else in its natural finish.

No matter what paint you use, it's not going to hold up. And when (not if) it begins to come off, be it via melting, dissolving or flaking; you're just going to have a jolly mess on your hands.

 

Rick cracks me up! :lol:

 

Santa Chacal came early this June with almost every cleaning/tuning part you could want for doing your carbs and YCIS passage. (Yes I know I could have made some of them or bought locally).



About 5 minutes ago I ordered: HCP18863SET4 Aftermarket Hitachi carb DELUXE COMPLETE REBUILD KITS, for use on all XJ650 (except Turbo), 1985-86 XJ700 air-cooled models, and all 1981-84 XJ750 air-cooled models. This newer kit has every "wear item" you'd need/want when breaking the rack with minor upgrades such as SS bowl drain screws with hex heads and better gaskets.

Surprisingly I managed NOT to cash a check from my last job (temp agency) and they sent me a letter so I can contact them and get a new check issued. WOOT $300 more dollars in my pocket... Errr Chacal's pocket now :lol:

 

Got lucky again. Apparently Connie's carbs (from a former forum member) were well taken care of before it sat for 2 years.

I broke free all of the rack rail screws (with impact driver) with minimal problems. (They are still snug and attached though).

All but one of the jets/brass things came out with normal screw drivers. I had to use a few impact hits and vice grips on one of them. (I'll probably try to swap out a replacement from another rack).

Nothing appears to be broken. In fact other than checking floats levels, cleaning the bowls and re-sync'ing the carbs were probably fine as is. Regardless, I'll use this opportunity to fully rebuild a rack using Chacal complete deluxe kit.

Oh yeah, #1 and #4 passed clunk test w/o even cleaning them (just took off the hats and removed the big springs). The other two clunk when they don't stick. So they need some cleaning/polishing but probably very little.

All of the other spring action and movement pieces move smoothly/crisply as well. (My eBay and Gab carbs don't and I don't know how bad my MAIN carbs are yet).

Here's a few more pictures for those that like them.

Organized but not yet soaking parts:


Not perfect but hardly gummed up:


Click for larger versions:


Unless I'm wasting time/money/parts (please tell me if I am) I'll do a complete tear down/clean/rebuilt over the week or next Saturday (my only day off). If a bunch of people think I should just CLEAN/Balance/Float adjust the carbs because they are so clean speak up NOW. I'd then save the rebuild kit for my MAIN set of carbs and have a spare ready to install.

Honestly I don't expect the Gurus to tell me to just partially clean, but I'm just asking

 

The answer lies somewhere between the "scatter gun" approach and just cleaning.

I would start with a basic "carb service" per the manual, but add the removal, cleaning, inspection and parts (o-rings) replacements on the pilot mixture screws.

Leave the rack together, DON'T soak it in anything, and do the rest of the service. Pull the outer throttle shaft seals (the only two you can get to) and inspect. If they're fine, don't break the rack until you're sure it's necessary.

CLEAN the carbs thoroughly; flush all the passages, and replace any necessary parts. Be careful, thorough and precise; and see where you stand afterward.

 

Buy a set of Tools like these:

http://www.amazon.com/SE-Dental-Tool-Se ... tal+scaler

Go after all that scale and particulate.
A loose piece of old gasket or varnish the size of a pin-head will clog a Pilot Jet or prevent the Cold Start Siphon Tube from metering fuel.

Merry Christmas!