Road Star Forum
Welcome, Guest
Please Login or Register.    Lost Password?
Re:2004 Roadstar blowing carb off manifold
Go to bottom Post Reply Favoured: 0
TOPIC: Re:2004 Roadstar blowing carb off manifold
#1019562
MidnightRide (User)
Fresh Boarder
Posts: 87
graphgraph
User Offline Click here to see the profile of this user
Re:2004 Roadstar blowing carb off manifold 5 Days, 20 Hours ago  
Hopcycle wrote:
yes sir checked all that. and yes the hypercharger mount to the heads, but the rubber boot has enough flex to still allow carb to blow off.

Yes but the carb is STILL supposed to have a clamp to hold it onto the manifold. If the clamp's not there then surely there will be huge vacuum leaks if nothing else.

I have the hypercharger as well but it's not designed to push the carb up against the manifold, only to mount to the outward side of the carb.

Is the metal clamp (like a giant hose clamp) still there? I'm sure it is but have to ask.

Oh and FYI if you hit the gold 'Quote' button in the lower right corner, rather than 'Reply', we can see which question you are actually responding to!
 
Logged Logged  
 
Last Edit: 2017/08/11 12:45 By MidnightRide.
 
-- Roads? Where we^re going, we don^t NEED roads... --


  The administrator has disabled public write access.
#1019568
jd750ace (User)
Front toward enemy
Platinum Boarder
Posts: 18621
graphgraph
User Offline Click here to see the profile of this user
Gender: Male jd750ace Location: Waxahachie Texas Birthdate: 1969-10-30
Re:2004 Roadstar blowing carb off manifold 5 Days, 18 Hours ago  
Cams looked good before the 400 miles and now it will barely run? Better pull those lifters back out and have a look. BTDT. Followed all procedures for breaking in new lifters on a used cam, ate them anyway. All new, all good, over 50K miles ago. Used Sealed Power HT2011 lifters.
Started with a ticking front that would not stop. Lifter would not pump up and stay, even on the bench. Does not happen often, but does occasionally.
 
Logged Logged  
 
  The administrator has disabled public write access.
#1019581
Hopcycle (User)
Fresh Boarder
Posts: 9
graphgraph
User Offline Click here to see the profile of this user
Re:2004 Roadstar blowing carb off manifold 5 Days, 16 Hours ago  
MidnightRide wrote:
Hopcycle wrote:
yes sir checked all that. and yes the hypercharger mount to the heads, but the rubber boot has enough flex to still allow carb to blow off.

Yes but the carb is STILL supposed to have a clamp to hold it onto the manifold. If the clamp's not there then surely there will be huge vacuum leaks if nothing else.

I have the hypercharger as well but it's not designed to push the carb up against the manifold, only to mount to the outward side of the carb.

Is the metal clamp (like a giant hose clamp) still there? I'm sure it is but have to ask.

Oh and FYI if you hit the gold 'Quote' button in the lower right corner, rather than 'Reply', we can see which question you are actually responding to!


Thanks for the heads up on the quote button!! I know my replies were confusing lol Yes the clamp is on andhas been very tight every time it blew the carb off.
 
Logged Logged  
  The administrator has disabled public write access.
#1019582
Hopcycle (User)
Fresh Boarder
Posts: 9
graphgraph
User Offline Click here to see the profile of this user
Re:2004 Roadstar blowing carb off manifold 5 Days, 16 Hours ago  
jd750ace wrote:
Cams looked good before the 400 miles and now it will barely run? Better pull those lifters back out and have a look. BTDT. Followed all procedures for breaking in new lifters on a used cam, ate them anyway. All new, all good, over 50K miles ago. Used Sealed Power HT2011 lifters.
Started with a ticking front that would not stop. Lifter would not pump up and stay, even on the bench. Does not happen often, but does occasionally.



I failed to mention I went with the sealed power lifters also. No indication before this issue such as the ticking. and removing the decompression solenoid and doing a compression check sort of gives me confidence the lifters haven't failed yet. but thank you for the thoughts
 
Logged Logged  
  The administrator has disabled public write access.
#1019700
texasscott1 (User)
Two of a kind
Platinum Boarder
Posts: 4414
graphgraph
User Offline Click here to see the profile of this user
Gender: Male
Re:2004 Roadstar blowing carb off manifold 4 Days ago  
It occurs to me that the backfire could be caused either by the exhaust valves not opening properly or the intakes not closing all the way. If there's exhaust pressure left in the cylinder then there's going to be a heck of a bang when the intakes open. Same if the intakes aren't closed all the way when the plugs fire.

The cam could be at fault (probably) or not having reamed the valve guides. 400 miles is about right for new lifters to wear down an old cam.
 
Logged Logged  
 


My 99 Standard Test Mule
Scott B.
  The administrator has disabled public write access.
#1019720
Ctkog (User)
Senior Boarder
Posts: 209
graphgraph
User Offline Click here to see the profile of this user
Re:2004 Roadstar blowing carb off manifold 3 Days, 18 Hours ago  
First of all from California

If you verified SVS, and mentioned not reaming the guides, and problem came back, couldn't it still be SVS causing the problem?
 
Logged Logged  
 


Nothing straightens my head out better than an entirely crooked road.
  The administrator has disabled public write access.
#1019724
Questcap (User)
Platinum Boarder
Posts: 7559
graphgraph
User Online Now Click here to see the profile of this user
Gender: Male Location: North Attleboro, MA Birthdate: 1954-03-22
Re:2004 Roadstar blowing carb off manifold 3 Days, 17 Hours ago  
I thought SVS was typically an exhaust valve issue, but it's sure sounding like an intake valve would be hanging up, don't it???
 
Logged Logged  
 
Sig Pic deleted - larger than 450 pixels and 50 kb
  The administrator has disabled public write access.
#1019727
Curt (Moderator)
Never to old to ride!
Moderator
Posts: 22358
graph
User Offline Click here to see the profile of this user
Gender: Male curt.switzer@outlook.com Location: The Colony, Texas Birthdate: 1943-11-24
Re:2004 Roadstar blowing carb off manifold 3 Days, 16 Hours ago  
SVS is caused by bad jetting. In my experience get rid of the hokey Hypercharger and get a real true air filter like a K&N filter. Rejet your carb to better jetting and remove the air jet that the HC calls to be installed. I had a HC long long ago and had many problems like you and I developed a SVS cure which the guys use. Got rid of the HC and rejetted my carb and all was good for many years to come. There are to many places for air leaks on the rubber boot on a HC and the air/fuel value changes to much and to be honest all they are is something to try and impress people who know nothing about bikes to start with. Just my .02 and if you need any information that used to be on my site just PM me you e-mail address here. here.
 
Logged Logged  
 
  The administrator has disabled public write access.
#1019730
Ctkog (User)
Senior Boarder
Posts: 209
graphgraph
User Offline Click here to see the profile of this user
Re:2004 Roadstar blowing carb off manifold 3 Days, 16 Hours ago  
Questcap wrote:
I thought SVS was typically an exhaust valve issue, but it's sure sounding like an intake valve would be hanging up, don't it???

You're right Questcap typically the exhaust, if too low quide clearance with heat. I agree it sounds more like would be the intake and don't know if intakes ever show SVS. I don't see why not if the clearances arent' met. And I think only early 1700s that had the problem.
 
Logged Logged  
 


Nothing straightens my head out better than an entirely crooked road.
  The administrator has disabled public write access.
#1019767
Hopcycle (User)
Fresh Boarder
Posts: 9
graphgraph
User Offline Click here to see the profile of this user
Re:2004 Roadstar blowing carb off manifold 2 Days, 23 Hours ago  
texasscott1 wrote:
It occurs to me that the backfire could be caused either by the exhaust valves not opening properly or the intakes not closing all the way. If there's exhaust pressure left in the cylinder then there's going to be a heck of a bang when the intakes open. Same if the intakes aren't closed all the way when the plugs fire.

The cam could be at fault (probably) or not having reamed the valve guides. 400 miles is about right for new lifters to wear down an old cam.


I haven't checked for the exhaust valves opening, but the leak down test gives me some level of confidence that the intake valves are closing. I should be able to install leak down tester, and rotate til exhaust valves should be open and see if I have air blowing out the exhaust. Thanks for the idea!
 
Logged Logged  
  The administrator has disabled public write access.
Go to top Post Reply
Powered by FireBoardget the latest posts directly to your desktop
...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... -->
New Forum Posts




The Road Star Clinic is a collaborative community of riders who archive and publish user contributed technical data about Yamaha Road Star motorcycles.

We also sponsor the creation and support of other community websites similar to our own. Inquiries about availability of a website for your community can be submitted to us via any "Contact Us" option on the Clinic.

Copyright 2003-2007 Road Star Clinic and its respective authors. Road Star Clinic is sponsored by the folks at MLSHomeQuest.com.