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Axelf
Posted on Tuesday, July 17, 2012 - 03:54 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Hello everyone. I'm new to the forum and to motorcycles! I bought my first bike, a 2003 Blast with 2600 miles, couple weeks ago. Learning from what i read on this and other forums I went ahead and did a tune up as there was no telling how long the bike sat before I bought it.

The issue is now I have what I THINK is a knocking when I give it gas. I really don't know what to listen for but it doesn't sound normal. It's louder than the exhaust and is only there when I gas it. I feel like other people can hear it when I drive by...<embarrassing>

Things done/replaced:

- Oil Change (Mobile 1)
- Spark Plug (gapped to .40) (old plug was dry and Black)
- Spark plug wire
- New intake boot
- Primary adjusted (tightened till heard whirring then backed off till no noise)
- Static Timing set so light goes off as SOON as the line enters window from left.
- Air/Fuel screw loosened 2.5 times from tight.

I don't know how to adjust timing to help with an engine knock. Assuming it's a timing issue.

Any help would be GREATLY appreciated.
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Gearheaderiko
Posted on Tuesday, July 17, 2012 - 04:53 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

That is not how timing is adjusted. Adjust the static timing per the manual.
What weight oil?
Are you using premium gas?
How many quarts of oil did you put in?
Do you have a manual?

FWIW: So you may pass this along, half of what you did was unnecessary. Ride the bike first then assess any issues. Yours is an all too common situation. Someone buys a bike and before they can really ride it they do a bunch of work to it and then end up with problems. I'm just happy you didn't take the carb apart "just to give it a good cleaning". Sorry if that seems negative but your situation happens A LOT.
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Gearheaderiko
Posted on Tuesday, July 17, 2012 - 04:59 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

PS there isn't ever any reason to adjust timing with an electronic ignition. Timing never changes, only parts go bad. I'm also quite sure it's a timing issue. Do not ride your bike until you fix it.

If you marked the module before you turned it, go back to the original setting.
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Axelf
Posted on Tuesday, July 17, 2012 - 05:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Gotcha. Another forum told me to adjust my timing so that is the only reason I did.

Just to certain i'm doing it right. the light should be on when mark is middle of window right?

What weight oil? 20w50 (V-Twin formula)
Are you using premium gas? Yes
How many quarts of oil did you put in? Just under two
Do you have a manual? No

(Message edited by Axelf on July 17, 2012)
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Axelf
Posted on Tuesday, July 17, 2012 - 07:02 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

It's entirely possible that what I'm hearing is not a knock and just a normal sound from the engine when gas is given to it.

The main reason most of that other stuff was done was to cure a real bad case of carb cough. Which for the most part is fixed... only coughs on cold start if i give it too much gas. But that's a another thread.

I'm going to bring the bike to a local bike shop tomorrow and see what they think.

It's all very frustrating lol

PS I set the timing according to the manual. Light is on when mark is top dead center.
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Axelf
Posted on Tuesday, July 17, 2012 - 09:39 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'll post back once the mechanic take a listen.

What type of things usually cause a knock when the bike is under strain?

I doubt it's the timing as I did exactly as the manual said. And the spark plug is brand new...unless it needs to be advanced or retarded. But that's over my head.

(Message edited by Axelf on July 17, 2012)
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Roblast
Posted on Tuesday, July 17, 2012 - 10:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I've spent lots of time and energy chasing a "ticking" sound in my bike that's apparent under load. I''d been told that it's "valve noise". I ride 50 miles each way on my back roads commute and I was worried it wasn't just noise and it would die in the middle of nowhere permanently wrecking itself. I tore down what I knew I could, checked timing, plug... All the stuff you're doing. Never found a problem. If you're told it's valve noise, believe them. FWIW - ping / knock supposedly sounds more metallic than valve noise.
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Gearheaderiko
Posted on Wednesday, July 18, 2012 - 10:51 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"the light should be on when mark is middle of window, right?" Yes. When the center line (straight line, not the 2 dots) is in the middle of the hole. Light should just come on when turning the module. You should only turn the module to check the LED, Not The Engine. Module should be in the same place as it was before you adjusted it.

"embarrassing" knock shouldnt happen. The second place to look would be the chain adjustment. I would default to the repair manual method going 12 flats instead of the 4.5-5 the manual says. Even going strictly by the manual, it wont make noise. Overly tight will also cause heavy knock (but it has to be really tight).

Did you use a factory spark plug wire? What spark plug?

Just to reiterate my previous frustration. A 2003 Blast with 2600 miles is basically a new bike. It shouldnt need anything. Please remember that if anyone tries to talk you into doing any more work. Please get a repair manual (or a pdf. if thats what you have). The Blast is a very simple motorcycle which few professionals seem to be able to repair properly. DONT TRUST ANYONE, before giving it a good think through or ask for a 2nd opinion. Reading up on repairs you may do or might pay someone to do is your best defense against future problems.

Please understand that many times what I write is under the assumption that you wont be the only one reading it. Some will read the entire forum and never post.
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Johneblast
Posted on Wednesday, July 18, 2012 - 07:33 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I have found that a knock under strain can also be bad fuel with not enough octane. Put some 92 (or I guess most places it's 91 now) and add a shot (and I mean a shot from a shot glass) and see if that helps. I let my bikes have a shot every once in a while. They seem to like it.
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Blackblue
Posted on Wednesday, July 18, 2012 - 07:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

quote RoBlast:
"I've spent lots of time and energy chasing a "ticking" sound in my bike that's apparent under load. I''d been told that it's "valve noise". I ride 50 miles each way on my back roads commute and I was worried it wasn't just noise and it would die in the middle of nowhere permanently wrecking itself. I tore down what I knew I could, checked timing, plug... All the stuff you're doing. Never found a problem. If you're told it's valve noise, believe them. FWIW - ping / knock supposedly sounds more metallic than valve noise."


I've been hearing this noise too, though I am really convinced it's probably the chain in need of adjustment and possibly a fluid change.
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Blackblue
Posted on Wednesday, July 18, 2012 - 08:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Also, from the Blast manual:

Primary Chain Adjustment
See Figure 6-4. Buell Blast Models are shipped with a spacer between the primary chain limiting screw and the locknut. The spacer is used to quickly get proper adjustment during production. This spacer should be removed and discarded at the first adjustment interval.
1. See Figure 6-5. Back-off locknut and chain limiting screw. Remove spacer.
IMPORTANT NOTE
Be certain to use Inch-Pound Wrench. Chain adjuster shoe can be damaged by excessive force.
2. See Figure 6-6. Tighten chain limiting screw to 24 in-lbs.
3. Back-off chain limiting screw 3/4 turn (4 1/2 “flats”). (GearheadErikO recommends 12 flats as indicated by the repair manual)
4. Hold chain limiting screw while tightening jam nut.
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Axelf
Posted on Wednesday, July 18, 2012 - 09:03 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

@Gearhead - thanks for the info man. And I understand you're not jumping all over me intentionally and these are issues that come up every other day. I'm sure you and everyone else are tired of hearing them. But thanks anyways for the heads up.

I put the module back in place. Checked the primary like 5 times. Each time making sure I followed the PDF. I did the 12 flats like Gearheaderiko said but no improvement. I know the bike is pretty new.. that's why I'm so frustrated.. it should'nt be having all these issues ...unless the previous owner f'd with everything.

The only reason I looked at the timing was that every thread dealing with engine knock said to check that. Otherwise I would never had messed with it. I was just trying to be proactive.

I've had the bike 3 weeks and haven't ridden it more than 3 days yet...

PS: It only gets high test gas and I've tried two brands so far. So reluctantly I'm ruling out fuel as the issue.
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Gearheaderiko
Posted on Wednesday, July 18, 2012 - 11:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

It is possible the PO f'd it up. I seen many Blasts with less than 2000 miles on them that have been completely molested : (

If someone overtightened the primary that will break the shoe and cause lots of noise. Usually though you cant get any kind of torque or adjustment out of it when the shoe is broken. FWIW: The average distance between the bottom of the adjuster bolt head and the top of the adjuster locknut (the threaded section showing) is about 1/4"-3/8". A new Blast I'd go 8 flats. A Blast with your mileage I'd go 12 flats and little more as the bike gets older. Beyond that I'd hope that you've got the "By Ear" method down and combining the 2 methods gets as close to perfect as you can get.

Early Blasts had an oil pump drive gear failure problem. Mostly 2000 models then decreasing as the bikes got newer. Your bike would run, be sluggish and makes lots of noise. However the telltale sign is that it always needs oil, until you've got about 4-5 quarts in it. When you wrote it "puked" lots of oil with the timing hole unplugged and the engine running, that raised a red flag for me. It sprays a lot, but if it pukes a lot, that says the crankcase is full of oil. Hence too much oil.

"Lugging" the engine will cause knock. Sometimes new Blast riders (whether new or just new to the Blast) are afraid to wind the engine out. It'll buck and shake and knock if you're lugging it. It'll do 32 mph in first gear before the rev limiter kicks in. 15-20mph is about the minimum you should shift at after its broken in. The rev limiter wont let you over rev and hurt the engine and mine'll do 40mph in first gear, so I assure you you wont hurt it by bouncing of the rev limiter occasionally!!

The Blast is noisy especially if you're sitting next to a Gold Wing or BMW. Sometimes that gets people a little freaked on the noise.

If you've got a bad engine mount, that will cause hard knocking. That would be if you're confusing engine knock with something knocking on the frame. Not hard to confuse the two, but if you know the difference, you know the difference. Its not hard to tell the two apart either.

If the gap on the spark plug got closed down on installation that can cause some issues (besides not running), but severe engine knock usually isnt it.

A bad intake boot or improperly installed intake boot can cause knock and ping. But thats usually in the mid to higher rpm range and you usually have hard starting associated with it.
But the further I get away from my first sentence is the likelihood that these issues would cause hard or embarrassing knocking.

The best thing is if you can find a Blast rider close to you and compare bikes. Thats a sure way to find out if you indeed have a problem and how severe it might actually be.
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Axelf
Posted on Thursday, July 19, 2012 - 11:33 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ok Mechanic said the timing was a little advanced and that may be causing the carb cough. He said the knock sounds like valve train noise and there isnt much he can do as nothing is adjustable.

He said not to worry unless it gets worse.

So i'm going to ignore the sound and focus on making the shifting stop GRINDING into 1st and 2nd. in a new thread of course!

Thank you very much for your help guys. And big thanks to Gearheaderiko
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Axelf
Posted on Thursday, July 26, 2012 - 04:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ok so it's been a solid week of driving since I had the bike looked at.

The knocking on acceleration is still there, and it's really annoying but I'm learning to live with it.

Sucks that a bike this new would have any sort of issue... but it's a bad draw I guess.

I will say one thing... this thing isnt lacking any sort power. I hit 90 without much issue. So if there is an issue it's not affecting the performance at least : )
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Ezblast
Posted on Thursday, July 26, 2012 - 05:29 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Heck I always recommend 14 to 18 flats out - lol
EZ
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