Farm boy’s Rattle-can Racer
- Thread starter farmer92
- Start date
farmer92
Coast to Coast
Playing dress up
Carbs cleaned (again)
Carbs on and plumbed
Pipes on
Striped Exhaust bolt hole fixed
Need to fill up fluids and set the timing.
Teazer, you wouldn’t be able to tell me how many degrees of a delay there are between the pickup coils being triggered and the spark firing by any chance?
I think timing this thing is going to be the trickiest part.
Carbs cleaned (again)
Carbs on and plumbed
Pipes on
Striped Exhaust bolt hole fixed
Need to fill up fluids and set the timing.
Teazer, you wouldn’t be able to tell me how many degrees of a delay there are between the pickup coils being triggered and the spark firing by any chance?
I think timing this thing is going to be the trickiest part.
farmer92
Coast to Coast
Borrowed a timing light and set the timing to 24* btdc as per manual. This ignition has a retard curve built in so we’ll see how it goes.
Had trouble with the tank petcock so rigged up a ghetto gas tank from an old water bottle haha.
Fired up before my foot was even finished kicking
Like a little kid in a candy store.
Candy
https://m.youtube.com/watch?v=a9Tx3_z_s9o
Left side smokes a touch heavy, gotta check into that.
Had trouble with the tank petcock so rigged up a ghetto gas tank from an old water bottle haha.
Fired up before my foot was even finished kicking
Like a little kid in a candy store.
Candy
https://m.youtube.com/watch?v=a9Tx3_z_s9o
Left side smokes a touch heavy, gotta check into that.
On the 250-350 ignitions we time them at 19 degrees BTDC as the pickups match the rotor lines. On a 54mm crank with 110mm rods that's around 1.85mm. the amount of retard is minimal.
On TZ250 J-K-L there was a more aggressive curve but I think it is also designed to fire at those marks at 10k revs. I never bothered to check what the timing looks like with a strobe or what the curve was. 1.85 worked best so that's where it stayed. With a modern programmable ignition I would time it to 19 degrees at peak torque dropping after that and more advance at lower revs up to say 24-26 degrees for more punch at low revs off teh pipe where compression is much lower and you need more advance.
On TZ250 J-K-L there was a more aggressive curve but I think it is also designed to fire at those marks at 10k revs. I never bothered to check what the timing looks like with a strobe or what the curve was. 1.85 worked best so that's where it stayed. With a modern programmable ignition I would time it to 19 degrees at peak torque dropping after that and more advance at lower revs up to say 24-26 degrees for more punch at low revs off teh pipe where compression is much lower and you need more advance.
farmer92
Coast to Coast
teazer said:
Thanks
When i stuck the strobe on it and kicked it over it would fire when the first of the three lines would line up with the pickup, so i set that at 24*.
It slowly retards 3-4 degrees on its way up the rpms, so it probably gets close to 19 at the peak. Not that i’ve tried to rev it up that high yet.
Having fuel delivery issues but i think i may have it solved now.
I don’t know who they were fooling with the cans on the ends of the pipes. They muffle nothing, and produce the most viscous sound i’ve heard from a bike in a long time.
farmer92
Coast to Coast
Had a chance to tinker a bit this afternoon.
Lots of backfiring, more evident when warmed up.
Both Through the carb and pipes.
It actually blew the pipe 1/2” off the manifold so i’m gonna need stiffer springs.
Mostly on deceleration, lean mixture?
I didn’t put any silicone on the pipe/manifold, is air getting in there and promoting some of the backfires?
Runs somewhat better with chokes on.
Spitting lots of fuel back out the carbs though.
Needs air filters
Needs everything without locktite locktited.
Needs clutch pushrod lengthened somehow
Brakes to bleed
Needs a tach
Lots of backfiring, more evident when warmed up.
Both Through the carb and pipes.
It actually blew the pipe 1/2” off the manifold so i’m gonna need stiffer springs.
Mostly on deceleration, lean mixture?
I didn’t put any silicone on the pipe/manifold, is air getting in there and promoting some of the backfires?
Runs somewhat better with chokes on.
Spitting lots of fuel back out the carbs though.
Needs air filters
Needs everything without locktite locktited.
Needs clutch pushrod lengthened somehow
Brakes to bleed
Needs a tach
farmer92
Coast to Coast
So after spending 220 hours living in a tractor for the last 2 weeks, we finally got enough rain to cause some down time.
Bought some coarse Uni foam filters
I know they are for snowmobiles and that they don’t filter down as small of a particle, but this thing used to run sans filter so it’s still a step up.
Fired the old girl up and rilled her around my yard. Poorly, pretty much on the left cylinder.
Killed it after about 30 seconds
Left plug seemed ok
Right plug was soaked.
Right plug was also the one backfiring like crazy.
After some inspections i noticed the pickup coil for the RHS had moved and was 5* further advanced than the left, probably close to 30* yikes.
Carbs are 36mm VM
Pilots are 40 mikuni
Mains are 310 mikuni
Bought some coarse Uni foam filters
I know they are for snowmobiles and that they don’t filter down as small of a particle, but this thing used to run sans filter so it’s still a step up.
Fired the old girl up and rilled her around my yard. Poorly, pretty much on the left cylinder.
Killed it after about 30 seconds
Left plug seemed ok
Right plug was soaked.
Right plug was also the one backfiring like crazy.
After some inspections i noticed the pickup coil for the RHS had moved and was 5* further advanced than the left, probably close to 30* yikes.
Carbs are 36mm VM
Pilots are 40 mikuni
Mains are 310 mikuni
Not much appreciation for these T500s. Glad to see another. Here’s my 73. Before and after
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Sent from my iPhone using DO THE TON
Attachments
farmer92
Coast to Coast
MMVEC said:
That looks pretty sweet
Did you do the pinstripes yourself? They add a nice touch
So this morning i realized again how much of an idiot i am.
It turns out, both sides have different delays from pickup trigger to spark, its about 6* in this case. So the RHS timing was not all that far off in the first place.
Either way, both sides are set to 19* btdc now.
But the RHS is still having trouble, and it’s spewing oily gas out the exhaust port like it’s going out of style. Replaced the plug and it runs with the throttle open, just doesn’t want to idle. Time for some carb cleaning.
LHS is pretty much perfect at this point.
farmer92
Coast to Coast
So after riding it back and forth through a field, it does seem to run quite well up to about 1/2 throttle. Unfortunately i haven’t had time to take it anywhere that the avons are better suited for. The gear ratios are stock at the moment with a 38 rear sprocket to make up for the reduced primary ratio.
Will probably switch to a 13 tooth counter sprocket vs the 15 that’s on there. That would be the equivalent of having a 38 rear on a standard machine, a modest 15% change.
I also started figuring out how this damn fairing was mounted.
I think i will leave the fairing as is, maybe replace the windscreen though, i like it’s been there done that look.
Will probably switch to a 13 tooth counter sprocket vs the 15 that’s on there. That would be the equivalent of having a 38 rear on a standard machine, a modest 15% change.
I also started figuring out how this damn fairing was mounted.
I think i will leave the fairing as is, maybe replace the windscreen though, i like it’s been there done that look.
CarbsAndCylinders
Careful With That Axe Eugene
I put a 13 tooth on mine and it made a significant improvement in acceleration but shifting into 2nd gear comes up a little too quickly.
You should get one of these: http://www.fastfromthepast.com/24-0010
You should get one of these: http://www.fastfromthepast.com/24-0010
farmer92
Coast to Coast
CrabsAndCylinders said:
Ya
I think my problem is less the acceleration part and more the lack of traction where i was testing it. Getting up to speed was no problem, the slowing down was the hard part. My neighbour has a nice dirt road down through his switchgrass fields, 2k long and he just finished grating it the other day. Going to see if he doesn’t mind me testing the bike there.
Will get a 13 and 14 tooth just to see.
As for the fork brace, the bike has 1986 FZ600 forks and the lowers have a bracket built in, i just need a chunk of Al with 4 holes in it, it will be covered.
CarbsAndCylinders
Careful With That Axe Eugene
This is so interesting to watch, can't wait for the start-up. 38mm carbs sound too big to me, most modded T500's I have seen have used 34mm, I think that at least the original TR500's used 34's, although Teazer would have made a comment on this if it was a problem.
Brian
Brian
