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Good mechanic in the Abbotsford area?
- Thread starter kagia
- Start date
Thanks, Grove.
I've received a bunch of advice from other forum members, and while it is all good advice, I've tried it all and am about done with it. I feel like I've gone as far as my limited mechanical skills will take me and I'm ready to just pay a good mechanic to get it squared away.
Basically, I installed a TM40 pumper carb, FMF Powerbomb header, Leo Vince X3 Enduro muffler, and opened up the airbox, and now it kinda runs like crap.
The decel popping is so loud and so excessive that I haven't even been riding it for probably the last month. The header also sometimes glows bright red after only a few minutes of riding. I figure this may be caused by a lean condition, but the bike has plenty of power through entire rpm range and throttle response is good. I've messed with the idle mixture as well as the idle speed and it doesn't seem to help.
Another thing that really bothers me is that since I installed the carb, the bike idles higher when sitting on the side stand than it does when the bike is upright. Nothing too crazy, but it is noticeable, and is actually enough to kill the engine when the bike is cold. Checked the cable routing and nothing seems to be binding/pulling/kinking. Idle doesn't change at all from lock to lock.
Anyway, I'm feeling pretty defeated and would just like to pay a good mechanic to see if he can get it dialed in. Doesn't necessarily have to be right in Abbotsford, but at least on this side of the Port Mann.
I've received a bunch of advice from other forum members, and while it is all good advice, I've tried it all and am about done with it. I feel like I've gone as far as my limited mechanical skills will take me and I'm ready to just pay a good mechanic to get it squared away.
Basically, I installed a TM40 pumper carb, FMF Powerbomb header, Leo Vince X3 Enduro muffler, and opened up the airbox, and now it kinda runs like crap.
The decel popping is so loud and so excessive that I haven't even been riding it for probably the last month. The header also sometimes glows bright red after only a few minutes of riding. I figure this may be caused by a lean condition, but the bike has plenty of power through entire rpm range and throttle response is good. I've messed with the idle mixture as well as the idle speed and it doesn't seem to help.
Another thing that really bothers me is that since I installed the carb, the bike idles higher when sitting on the side stand than it does when the bike is upright. Nothing too crazy, but it is noticeable, and is actually enough to kill the engine when the bike is cold. Checked the cable routing and nothing seems to be binding/pulling/kinking. Idle doesn't change at all from lock to lock.
Anyway, I'm feeling pretty defeated and would just like to pay a good mechanic to see if he can get it dialed in. Doesn't necessarily have to be right in Abbotsford, but at least on this side of the Port Mann.
Don't have all the answers for ya, nor am I trying to keep you from getting a good mechanic........but decel popping is not an issue by itself, my DRZ does that...as is a glowing header. My header will glow cherry red at idle....little to no airflow and it isn't all that thick....so why wouldn't it?
A little more effort with the pilot circuit (pilot jet sizing) would reduce the decel popping, if you think it necessary.
You say it runs like crap, but then sort of contradict that later("the throttle response is good"?
Good luck with the bike, riding time is getting pretty short!
A little more effort with the pilot circuit (pilot jet sizing) would reduce the decel popping, if you think it necessary.
You say it runs like crap, but then sort of contradict that later("the throttle response is good"?
Good luck with the bike, riding time is getting pretty short!
Grove
New member
Oh the joys of figuring out jetting and your air/fuel mixtures after you change everything.............ya I totally get why you are looking for someone to sort it out.
I had that nightmare with my old GPZ750...........it was operational but finicky at best.......I just gave up and sold it to a guy who knows those motors inside out.
Best of luck.........tho I will say Clint over at International Motorsports in Langley knows thumpers and lots of other bikes really well, just talking in person with him about my GPZ750 he got my jetting mostly figured out without ever seeing the bike and only going by symptoms I mentioned to him.
Hope ya get it sorted, I know your pain buddy.
I know! That's why I would rather just pay to have it done properly and quickly instead of tinkering around with this and that until the season is over. Thinking about maybe going up one size with my main jet today when I get home, but other than that, I don't know what else to do.
Before all my mods, it did pop a bit, but it was what I would consider very tolerable. Now though, it is very excessive and LOUD.
Yeah I almost wish I'd left it stock. I might try swapping out my main jet today after work, but if that doesn't work, maybe I'll haul the bike out to International.
....If it even fits in the tiny box of this new truck.
Main jet size should not have an effect on decel popping, however pilot jet should have some impact. Could the added noise be attributed to the change in the exhaust system? Jetting is generally set by power delivery, if by seat of the pants and fuel/air ratio if on a dyno. The real question is....how does the bike run once warmed fully?
Feel your frustration, been there a time or two myself!
Feel your frustration, been there a time or two myself!
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cactusreid
Active member
I just re-read your thread, and you may want to not bother reading my reply, but hey who knows, to each his own.
kagia, these guys are here to help you! And many of us have dropped $100.00 plus per hour for a professional, only to have to go home and sort it out for ourselves! I also feel your frustration, as I've also been there but you will be more annoyed if you drop a bunch of bucks and then still have to turn back to this forum to help solve your issue. And you will pick up vast amounts of info knowledge and intel if you learn and comprehend this stuff as you go through the paces! Jetting- is delivering the right amount of fuel to the engine at the right time in relation to the rpms and load that it is under over the rpm range that it operates at. Break it down to bite size pieces if your willing to jump in and get your head around it. First make it idle, then make the midrange rpms respond how you would like the bike to preform. then make the high rpm wide open throttle position give you as much yank as you care to squeeze out of your engine.
here are some quick and simple explanations- (don't trash me guys` I'm giving the simple not the detailed version here)
idle to approx. 1-eighth throttle- pilot jet and fuel screw setting on a 4 stroke motor
1-eighth throttle till approx. 1half throttle (damn keyboard won`t do the slash for me tonite) is governed by the needle type and diameter and the clip position -Ie how fat the needle is and how much taper it has and how deep it is down in the main jet and how fast it is being pulled out of the main jet.
Only after the needle is pulled mostly out of the main jet, does the engine really get to find out how big the main jet really is.
That being said each of these circuits low, mid and high rpms overlap each other so you need to be aware of this.
example- if you are way to big on the main, this will make everything to rich, as there will always be to much fuel flowing past the needle that is trying to plug up the main jet at mid and low range throttle openings.
I`m thinking one of these guy`s will get back to you soon with some base line jetting settings to try on your bike.
kagia, these guys are here to help you! And many of us have dropped $100.00 plus per hour for a professional, only to have to go home and sort it out for ourselves! I also feel your frustration, as I've also been there but you will be more annoyed if you drop a bunch of bucks and then still have to turn back to this forum to help solve your issue. And you will pick up vast amounts of info knowledge and intel if you learn and comprehend this stuff as you go through the paces! Jetting- is delivering the right amount of fuel to the engine at the right time in relation to the rpms and load that it is under over the rpm range that it operates at. Break it down to bite size pieces if your willing to jump in and get your head around it. First make it idle, then make the midrange rpms respond how you would like the bike to preform. then make the high rpm wide open throttle position give you as much yank as you care to squeeze out of your engine.
here are some quick and simple explanations- (don't trash me guys` I'm giving the simple not the detailed version here)
idle to approx. 1-eighth throttle- pilot jet and fuel screw setting on a 4 stroke motor
1-eighth throttle till approx. 1half throttle (damn keyboard won`t do the slash for me tonite) is governed by the needle type and diameter and the clip position -Ie how fat the needle is and how much taper it has and how deep it is down in the main jet and how fast it is being pulled out of the main jet.
Only after the needle is pulled mostly out of the main jet, does the engine really get to find out how big the main jet really is.
That being said each of these circuits low, mid and high rpms overlap each other so you need to be aware of this.
example- if you are way to big on the main, this will make everything to rich, as there will always be to much fuel flowing past the needle that is trying to plug up the main jet at mid and low range throttle openings.
I`m thinking one of these guy`s will get back to you soon with some base line jetting settings to try on your bike.
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Island Hopper
New member
As mentioned, your float height sounds to be off and that plays a big part in carb tuning... Your float is set to close off incoming fuel too soon leaving a fuel level in the bowl that is too shallow, which will cause a lean condition, especially at the lower rev range... I have not set up a TM 40 before, but it is probably similar to the BST 40 you took off as far as float adjustment is concerned...Having the bottom of the float parallel with the bowl gasket surface when the metal float tang is just touching the plunger on the needle but not depressing it will get you into the ballpark...
Do-Boy
New member
Hi Kagia, I totally empathize with carb issues! Which is why i swore them off lol. Anyways, with my old yamaha that was modified, I did it the hard way by trial and error on my own. If i were to do it again, I would look into the dynojet kits that they offer. It takes into account modifications. They send you a kit of jets so that you will definitely be in the ballpark. They are very reasonably priced too. Maybe check into this is you think at all that you still want to give this a crack.
http://www.dynojet.com/pdf/3138.pdf
http://www.dynojet.com/jetkits/motorcycle/jetkits.aspx?vt=motorcycle&vm=suzuki
http://www.dynojet.com/pdf/3138.pdf
http://www.dynojet.com/jetkits/motorcycle/jetkits.aspx?vt=motorcycle&vm=suzuki
I know a good professional mechanic that fixes these issues all day long. The problem is no one likes to listen to his advice. So he does not handle retail work anymore.
But there are occasions he may take on a special project now and again. He has made several posts on jetting and electrical diagnostics and you may find some info on past posts.
He is not a Google/You tube technician and does not repair by rote. He has a 35 year track record and resides in the lower mainland. The free advice this morning is that you cannot properly jet any machine without a dyno.
But there are occasions he may take on a special project now and again. He has made several posts on jetting and electrical diagnostics and you may find some info on past posts.
He is not a Google/You tube technician and does not repair by rote. He has a 35 year track record and resides in the lower mainland. The free advice this morning is that you cannot properly jet any machine without a dyno.
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Ti welder
New member
As mentioned above.... Without a dyno, and because of epa regs, it's a trial and error game
I am not sure who said it to me but was likely someone here,"those guys in the white lab coats know what they are doing at the factory"
sometimes to meet regulation, engines are purposely mistuned
that said, modifications may produce slightly more power under ideal conditions, that doesn't mean everything will work ideally! Most aftermarket pipes, carbs, cams, ect, claim more power but reliability usability suffer for that extra one or two % power
Trying to get blood out of a stone sometimes requires a trip to the gravel pit for a different rock!
From what you have done for air delivery, you need more fuel, much more! And don't forget, the thing was prolly set up quite lean for emission regs to start with
Good luck with it!
Just my babble.....
I am not sure who said it to me but was likely someone here,"those guys in the white lab coats know what they are doing at the factory"
sometimes to meet regulation, engines are purposely mistuned
that said, modifications may produce slightly more power under ideal conditions, that doesn't mean everything will work ideally! Most aftermarket pipes, carbs, cams, ect, claim more power but reliability usability suffer for that extra one or two % power
Trying to get blood out of a stone sometimes requires a trip to the gravel pit for a different rock!
From what you have done for air delivery, you need more fuel, much more! And don't forget, the thing was prolly set up quite lean for emission regs to start with
Good luck with it!
Just my babble.....
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cactusreid
Active member
Dyno jetting would probably be the optimum, I agree. Not many of us have access to one though? But lots of us have carbed bikes with and without performance parts/mods done, that will flash to life before the starter stops spinning, idle strong and cleanly and pull hard through the rpms with nary a stumble or a hiccup all the way to wide open throttle. JD jetting kits, and online support and advise is how I get my bikes to preform like this.
Individual results may vary? You get back what you put in, and have available to you.
Individual results may vary? You get back what you put in, and have available to you.
Do-Boy
New member
define "properly."
Ideally or optimally, sure. But there is a history of thousands upon thousands of people that have successfully rejetted a car or motorcycle without a dyno. Myself included. I was able to learn from resources like youtube and google to modify my old bike, then rejet it to start every kick and run with more power than stock and better throttle response. Sure it would have been quicker to be able to test on a rolling road. But your original claim is pretty condescending and negative. I don't mean to brag here, but I want to motivate people who do have a desire to tackle issues.
Have to agree with cactusreid and do-boy, much can be accomplished with a bit of homework and little trial and error. My bikes have never seen a dyno but they don't seem to know that !
I get Vortexman's point about the dyno, but I will say it isn't necessary to get a bike running well.
I get Vortexman's point about the dyno, but I will say it isn't necessary to get a bike running well.
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DirtClunker
Active member
Hope you get it srted. That TM40 is a great improvement to the DR650.