Back fire through the throttle body? - Club700XX - Honda TRX700XX Forum
User Tag List

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 13 Old 08-29-2016, 12:12 PM Thread Starter
Member
 
Join Date: Mar 2014
Posts: 32
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Back fire through the throttle body?

My bike was running great this weekend, until at the very end I felt kinda like a back fire under the seat in the air box. The bike wouldn't crank any more after that. Just a few minutes ago I stopped by the house on lunch break and thought I'd try to turn her over a little bit and she wouldn't start. After a few times holding the starter, it like back fired with enough force to separate the throttle body from the rubber boot it connects with... What the hell?
Jgspahn is offline  
Sponsored Links
Advertisement
 
post #2 of 13 Old 08-29-2016, 05:57 PM
Senior Member
 
Join Date: May 2015
Posts: 591
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Garage
timing chain ?

751 ,barker pipe,290 Web cam,+3 stroker,TB bored to 46.8 and moved back from head 1 inch,+3 big bore , +1 intake valves, Hard Welded Rockers,KW springs, ported, clutch mod , air box removed ,Cat oil mod, dynojet commander V w/auto tune , lowered rear end , TRX450R front shocks ,
cataway is offline  
post #3 of 13 Old 08-29-2016, 09:43 PM

 
M_Quick's Avatar
 
Join Date: Jan 2011
Location: Columbus, Oh
Posts: 5,669
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 242 Post(s)
Garage
My guess would be a valve issue, and you've been down that road before I think.

#1 2008 Honda Trx700xx HMF Performance Exhaust, PCV, Stroked 710cc, 10.5:1 Wiseco Piston, Frt Elka Stage 4's, Fox Podium X rear's, EHS Lid, L8ton 11/16" sway bar, PRM Desert II Bumper & Front Skids.
#2 2008 Trx700xx AMR Reaper, Ehs Big 3, P/P head, Xcalibur Cam, Hard Welded Rockers, +1 In/Ex Valves, +3 Throttle body, 11:1 CP Piston, Elka Stage 3 Legacy Shocks, L8ton 11/16th Sway Bar, PRM Front Skids, Desert II Bumper & Rear Utility Rack.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
M_Quick is offline  
 
post #4 of 13 Old 08-30-2016, 07:58 AM
Senior Member
 
Join Date: Sep 2014
Location: Eastern PA
Posts: 215
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 57 Post(s)
I can actually feel mine backfire once in a while (not too often, but I feel the seat move!) I usually just wait a little bit and it starts right up. I was kinda guessing valves, but since it always starts I haven't anything yet.
mumbauer is offline  
post #5 of 13 Old 08-30-2016, 07:42 PM
Member
 
bevans143's Avatar
 
Join Date: Aug 2010
Posts: 38
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
I had the same problem. I changed the plug and it fixed it. Mine runs a little rich. It may be just a fouled plug.
bevans143 is offline  
post #6 of 13 Old 08-30-2016, 08:50 PM Thread Starter
Member
 
Join Date: Mar 2014
Posts: 32
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
I checked valves today, they seem to be dialed in. Timing also seems to be good. I have fuel to the injector. I have a new spark plug I'll try tomorrow.

I have been having decomp issue, and when I touched the decomp on the cam it doesn't seem to have any during spring to it. If changing the plug doesn't help im gonna disassemble the cam.. I currently have the head cover off so I may do it anyway.

Any other help, suggestions, or info?

Could decomp cause the backfire and no start? Bc I thought it just caused hard start..
Jgspahn is offline  
post #7 of 13 Old 08-31-2016, 05:01 AM
Senior Member
 
Join Date: May 2015
Posts: 591
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Garage
disassemble the cam ? I don't know what good that will do . its not like you can get any parts for it.

751 ,barker pipe,290 Web cam,+3 stroker,TB bored to 46.8 and moved back from head 1 inch,+3 big bore , +1 intake valves, Hard Welded Rockers,KW springs, ported, clutch mod , air box removed ,Cat oil mod, dynojet commander V w/auto tune , lowered rear end , TRX450R front shocks ,
cataway is offline  
post #8 of 13 Old 09-02-2016, 10:17 PM Thread Starter
Member
 
Join Date: Mar 2014
Posts: 32
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Well I'm at a loss, I have no idea where to go next. I have fuel, I have a new spark plug, timing is on point, valves are on point.. only thing I can think of is some sort of decomp issue or something.. guess only step is to buy a new cam or something.. hell I dunno.. really wanted to ride this weekend :(
Jgspahn is offline  
post #9 of 13 Old 09-03-2016, 04:44 AM
Senior Member
 
Join Date: May 2015
Posts: 591
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Garage
decomp works off the exhaust side . maybe you had a hot spot

751 ,barker pipe,290 Web cam,+3 stroker,TB bored to 46.8 and moved back from head 1 inch,+3 big bore , +1 intake valves, Hard Welded Rockers,KW springs, ported, clutch mod , air box removed ,Cat oil mod, dynojet commander V w/auto tune , lowered rear end , TRX450R front shocks ,
cataway is offline  
post #10 of 13 Old 09-05-2016, 09:06 AM Thread Starter
Member
 
Join Date: Mar 2014
Posts: 32
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Well guys after hours and hours of jacking with this thing, it just magically cranked yesterday.. I hate mechanicing lol
Jgspahn is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Club700XX - Honda TRX700XX Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome