G oog le BadWeB | Login/out | Topics | Search | Custodians | Register | Edit Profile


Buell Forum » THUMPer Forum » Buell Blast Thumper Knowledge Vault » Engine - all topics related to the Motor » Backfire blew off carb! « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Johnglover
Posted on Tuesday, June 10, 2014 - 10:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Well, like the title says, I rode into town, got back and killed the bike. Then started it back up to move it around to the other side of the driveway (well I tried to). When it fired up it backfired hard and the stock airbox hit me in the leg. Smoke and liquid fuel were in the airbox (I think I may have unintentionally flooded it a bit getting back onto the bike).
Long story short, I Looked down at the airbox and noticed das boot was separated from the motor. My boot was in decent shape, I suppose the vibrations may have loosened up up the clamp. I don't know. Do I really have to buy the stock part if I want to replace it? Or can I find something that matches up perfectly at a hardware or automotive shop? If I don't want to replace the boot can I just readjust and tighten back down? Any recommendations?
Top of pagePrevious messageNext messageBottom of page Link to this message

Ezblast
Posted on Wednesday, June 11, 2014 - 03:28 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Either replace it with a stock part or Dan's super boot - anything else will just cause you trouble down the line - the stock boot is cheap - lol - don't go cheap on a inexpensive part - begging for trouble to do so.
EZ
Top of pagePrevious messageNext messageBottom of page Link to this message

Gearheaderiko
Posted on Wednesday, June 11, 2014 - 08:50 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Check the boot for rips or splits. If none, you can bolt it back on, but check it carefully.
Stock part or Dans boot only (concur!)
Top of pagePrevious messageNext messageBottom of page Link to this message

Johnglover
Posted on Wednesday, June 11, 2014 - 05:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Gotcha I'll take a look after work, and update hopefully with success
Top of pagePrevious messageNext messageBottom of page Link to this message

Johnglover
Posted on Wednesday, June 11, 2014 - 07:36 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Took off the boot, no cracks or splits. So I put it back on and tightened it up. And it may just be in my head but it seems to be running alot smoother. In hindsight, should I have put any sort of antiseize, grease etc.?
Top of pagePrevious messageNext messageBottom of page Link to this message

Gearheaderiko
Posted on Thursday, June 12, 2014 - 09:20 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

No. Nothing at all.
Top of pagePrevious messageNext messageBottom of page Link to this message

Nimbly
Posted on Sunday, June 15, 2014 - 12:25 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Have you changed anything that may have caused you to need to rejet. I had the same thing happen. Rejet my bike and no backfires anymore
Top of pagePrevious messageNext messageBottom of page Link to this message

Johnglover
Posted on Monday, June 16, 2014 - 07:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Nope nothing at all. However I have a new problem after a long ride in the rain, which I will take to anotger thread.
Top of pagePrevious messageNext messageBottom of page Link to this message

Chipmyers
Posted on Sunday, September 13, 2015 - 09:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

This looks like a good place for this. My Super Boot poped off today. Luckily I was able to coast into Tractor Supplys parking lot, and $11.00 worth of cheap tools later was back on the road. When I upgraded Dan's boot and intake I searched to forums for info and went the carb spring route and have not had any trouble until today. At some point the spring sprung and today it failed. Now, I have not been very diligent checking the tightness, and do not fault the boot at all, but I never was happy with the spring to the head deal, so here is what I whipped up in the garage tonite. If it works, I am sure I will clean it up some but it is solid as a rock. Anybody else try something like this????

Top of pagePrevious messageNext messageBottom of page Link to this message

Gearheaderiko
Posted on Sunday, September 13, 2015 - 10:39 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

That's bad. You've got a rubber mount carb braced solidly to the engine. While the SuperBoot is a fairly rigid mount, it's still rubber based. Something will eventually crack. Could be the brace or starter mount or elbow or ?!
Better to fix the cause of the backfire first, that's not normal.


FWIW: I've never run a brace or springs with an unsupported carb and stock boot. I also rarely have a backfire and have never had a carb blow off. Only one split boot after several hundred miles on some bad bumpy roads (with stiff suspension). The boot didn't shut the bike down, but I knew it probably split because I started to get exceptionally good gas mileage running at 90+ mph for about an hour!!

(Message edited by Gearheaderiko on September 13, 2015)
Top of pagePrevious messageNext messageBottom of page Link to this message

Gearheaderiko
Posted on Sunday, September 13, 2015 - 11:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

http://www.jpcycles.com/product/7400035

Common Harley rubber mount. Couple of L bends in that bracket and you're good!
They also come male/female (stud on one side, hole on the other). Provides an easy way to rubber mount/insulate parts. And cheap!
Just an idea. There are other rubber mounts available, but these are cheap and easy!
Top of pagePrevious messageNext messageBottom of page Link to this message

Gearheaderiko
Posted on Sunday, September 13, 2015 - 11:21 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)



Top of pagePrevious messageNext messageBottom of page Link to this message

Chipmyers
Posted on Monday, September 14, 2015 - 06:16 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Looks Perfect.
Thanks
Top of pagePrevious messageNext messageBottom of page Link to this message

Chipmyers
Posted on Wednesday, September 16, 2015 - 07:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Believe I had determined the reason the Super Boot failed. My last work rotation, I work on a cable ship and do 30 on and 30 off,my wife let our son in law borrow the blast while his car was broken to get to work.
He confessed to turning the blast into a super moto chasing his kids around his grand fathers farm on their 4 wheeler s and the boot coming off the intake. They stuck it back and tightened down with a crescent wrench and did not worry after it worked for a couple of hundred miles.
I took the carb off and reinstalled it,while waiting for the insulators to get here,250 miles with out an issue.
So I guess the don't jump ramps with a blast.
Top of pagePrevious messageNext messageBottom of page Link to this message

Ezblast
Posted on Friday, September 18, 2015 - 05:33 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

First - that HD rubber mount is what I used for the rear mounting for the Force exhaust - a nifty piece to know about, second - you can do that stuff but be prepared for the maintenance that goes along with it - repair/replacing front and rear isolators, and das boot. I gues if you do it for a living you really don't care - it's just part of maintenance - aka - Bubba Blackwell, but if your doing it for giggles - you might want to reconsider.



EZ
Top of pagePrevious messageNext messageBottom of page Link to this message

Chipmyers
Posted on Friday, September 25, 2015 - 07:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So the insulators arrived the other day, and I got a chance to mess around with it. Great Idea BTW. Very crude first attempt, but allows the carb to flex with the engine. The weather here is rubbish for the next few days, so my plan is to tack it together after a few more wacks at it and have our machinist fab one out of stainless stock when we go back out on the 30th, if it works that is. As usual this is a plea for guidance and advice. Thanks again.

Top of pagePrevious messageNext messageBottom of page Link to this message

Gearheaderiko
Posted on Friday, September 25, 2015 - 07:48 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

You learn what works and what doesn't by trial and error and the knowledge gained from that is applied on further modifications. I wouldn't use that rubber mount for an exhaust, but there are lots of rubber mount options out there. Better would be to sandwhich that mount between two L brackets with the bolts vertical (so the weight of the carb compresses the rubber mount instead of the weight resting on the bolts, tearing or shearing at the rubber mount). Not that those mounts aren't used in exactly your fashion on stock Harley products.

It does help to have a lot of experience knowing what's available in rubber mounts. The above method isn't the only way to rubber mount, but at $2.99 and being readily available, it's a quick and easy choice. One example is you could do the same thing with rubber well nuts. But they are a little more $$ and not really a good choice for that mount. But they have excellent other uses!!
Top of pagePrevious messageNext messageBottom of page Link to this message

Chipmyers
Posted on Saturday, September 26, 2015 - 11:48 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Yea! Keep it simple stupid!! 3 am I woke up and did this. My machinist used a term for me generally saved for out of town "footballers" when he saw the picture of what I did first. I think is more along the lines of a working prototype to work from

Top of pagePrevious messageNext messageBottom of page Link to this message

Gearheaderiko
Posted on Saturday, September 26, 2015 - 02:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Very nice! I *think* you'll have more longevity with that. Key word "think"! You can never be sure if something will stand the test of time, without putting in the time!
The engine bracket I made for my XB head I didn't think would last at all. It has shown zero signs of fatigue though after thousands of miles!
« Previous Next »

Add Your Message Here
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username: Posting Information:
This is a public posting area. Enter your username and password if you have an account. Otherwise, enter your full name as your username and leave the password blank. Your e-mail address is optional.
Password:
E-mail:
Options: Post as "Anonymous" (Valid reason required. Abusers will be exposed. If unsure, ask.)
Enable HTML code in message
Automatically activate URLs in message
Action:

Topics | Last Day | Tree View | Search | User List | Help/Instructions | Rules | Program Credits Administration