Thinking I may have a fuel starvation issue, as the supply tube had a slight uphill to the carbs. Shortened and re-route the tube. It’s all down hill from here!
ACBUILD
ACBUILD
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WELSH FLAT TRACK REVIVAL
- Thread starter Adamc
- Start date
Went back over @jpdevol suggestion.
OK returned to the carbs and decided to disassemble and clean yet again; no issues found.
On reassembly I did the slide drop test; and low and behold the left slide was just falling too quickly.
Took out the slide again and rechecked the diaphragm with a very bright Milwaukee LED pen light:
A tiny pin prick hole in a crease of the diaphragm; easily missed.
I'm hoping I have found the issue now with getting over 1/4 throttle.
I will have to source a new diaphragm / slide to fix this.
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ACBUILD
The two new slide / diaphragm arrived today from Yambits.co.uk. Had to swap the needles from the old to the new ones.
Quality seems to be as good as the ones that came out. Diaphragm of new one is much more pliable.
Unlike us older males, it seems hardness is due to age!
All simple stuff to do really. Bench checked the carb sync settings and mix screws.
Refitted carbs to the bike and fired up first go. Warmed the old girl up and knocked off choke.
Idle still good. Rev up through the ranges and slides are rising and falling as intended.
All the above done on the paddock stands. Test ride tomorrow.
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ACBUILD
Attachments
NEW RUBBER DIDN'T ERASE THE ISSUE!
Due to poor running I investigated the carb slide diaphragms suggested by @Jim and @jpdevol.
The 'Slow Slide Drop' test showed a problem with the left slide; It didn't drop slowly.
Removed the carb set, disassembled and cleaned the jets again.
Inspected the slide rubbers and discovered a tiny pin hole in the rubber diaphragm.
Ordered some new slides with rubber from Yambits.co.uk.
They arrived on Thursday. I swapped out the needle old to new slide; and I installed carbs on Friday.
Out for a short test ride on Saturday over varied roads around my shop. Up hill, down hill; fast and slow roads.
Gradual throttle application and quick application showed great results, just a little momentary fluffiness through half travel of the throttle.
I was happy with the results, knowing I may need to fine tune the jetting to the exhausts and Uni Filters.
Returned to the shop with a big grin; confident the bike would now get me to a destination.
Sunday I planned a route to a bike gathering in Abergavenny; a round trip of 80 miles on picturesque A & B roads.
Kitted up, Bike properly warmed up, choke off and away.......
30 meters along the road and shes not going too well, feeling a little bogged down. 2 miles along and shes popping and banging; and running like
worse that before the swap. Aaaaarggghhh!!!! Returned to the shop; put her away and went to the pub 
.Back at the shop today to go through the tests again; remove the carbs to investigate yet again.
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ACBUILD
As the carbs are off, yet again!
I did a compression test with my new compression tester thingy.
A cold one due to the above; no oil in the bores.
I got 130psi on both sides; I think I'm good with that.
ACBUILD
I did a compression test with my new compression tester thingy.
A cold one due to the above; no oil in the bores.
I got 130psi on both sides; I think I'm good with that.
ACBUILD
Thanks JP it’s great to know you guys watch my back. I’m no mechanic, just a guy trying to solve problems with logic and forum support.
ACBUILD
OK carbs are refurbished again with new slides & diaphragms; cleaned and reinstalled after bench set up. Carb boots have new gaskets; left side old one seemed perished when removed. Everything is buttoned up and ready to go. Battery on charge. Test tomorrow.NEW RUBBER DIDN'T ERASE THE ISSUE!
Due to poor running I investigated the carb slide diaphragms suggested by @Jim and @jpdevol.
The 'Slow Slide Drop' test showed a problem with the left slide; It didn't drop slowly.
Removed the carb set, disassembled and cleaned the jets again.
Inspected the slide rubbers and discovered a tiny pin hole in the rubber diaphragm.
View attachment 245547
Ordered some new slides with rubber from Yambits.co.uk.
They arrived on Thursday. I swapped out the needle old to new slide; and I installed carbs on Friday.
Out for a short test ride on Saturday over varied roads around my shop. Up hill, down hill; fast and slow roads.
Gradual throttle application and quick application showed great results, just a little momentary fluffiness through half travel of the throttle.
I was happy with the results, knowing I may need to fine tune the jetting to the exhausts and Uni Filters.
Returned to the shop with a big grin; confident the bike would now get me to a destination.
Sunday I planned a route to a bike gathering in Abergavenny; a round trip of 80 miles on picturesque A & B roads.
Kitted up, Bike properly warmed up, choke off and away.......
30 meters along the road and shes not going too well, feeling a little bogged down. 2 miles along and shes popping and banging; and running like
Back at the shop today to go through the tests again; remove the carbs to investigate yet again.
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ACBUILD
This morning checked the cam chain tension. All good.
Wiring up a three pin quick connector for the rear lights mounted in the seat unit.
What with my running issues the seat comes off every three minutes!!!
ACBUILD
Wiring up a three pin quick connector for the rear lights mounted in the seat unit.
What with my running issues the seat comes off every three minutes!!!
ACBUILD
A quiet moment in work so:
Swapped out the NGK non resistor plugs for brand new correctly gaped NGK resistor plugs with appropriate non-resistor NGK caps.
Checked valve clearances and all are OK.
Fresh tank of Shell V-Power E5
I think i have covered all other bases. @jpdevol and @Jim believe it could be a failing TCI unit.
Giving the old girl the best chance to run well. If the same popping & banging returns it looks like a new or reconditioned TCI unit for me.
Cliff (@nighthog) sent me a contact who can recondition the unit.
I'm hoping it runs OK.
ACBUILD
Swapped out the NGK non resistor plugs for brand new correctly gaped NGK resistor plugs with appropriate non-resistor NGK caps.
Checked valve clearances and all are OK.
Fresh tank of Shell V-Power E5
I think i have covered all other bases. @jpdevol and @Jim believe it could be a failing TCI unit.
Giving the old girl the best chance to run well. If the same popping & banging returns it looks like a new or reconditioned TCI unit for me.
Cliff (@nighthog) sent me a contact who can recondition the unit.
I'm hoping it runs OK.
ACBUILD
Pops, Bangs and bogging!
Another day another test ride.
Beautiful day in Cardiff; too hot for me to be honest.
Quiet in the shop today, so decided to take the bike out for another run to see if my latest handy work cured the issues.
Bike is looking awesome in the sunshine.
Immediate fire up as usual. Warmed the old girl up; knocked off the choke to a steady idle. Sounding real nice.
Took off down the 1/2 mile service road gently at first, snicking up the box nicely at quarter throttle.
Back down the road good throttle response and half throttle OK before backing off; one pop on closed throttle to a stop.
Onto main road and again half throttle with strong acceleration up hill. Down the other side and all running fine.
Left turn back towards shop and full throttle attempt; more pops and bangs and then bogging down.
Turning into shop car park and shes still bogging. Close throttle and nice even idle.
Park up and switch off.
Time to look at a new TCI unit (maybe borrow a spare one from a member, @nighthog and @jpdevol offered).
If it runs fine with another TCI; I will get mine refurbished / or GONZO job.
Its gotta be electrical now surely?
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Post in thread 'What have you done to your XS today?'
https://www.xs650.com/threads/what-have-you-done-to-your-xs-today.32082/post-798572
https://www.xs650.com/threads/what-have-you-done-to-your-xs-today.32082/post-798572
Start a build thread put a tag on every post you want to move there let me know, and I'll move posts for you
tag all posts you want to move exactly the same; something like acbuild, just edit and add it as a last line of the post.
then I can easily find and move the posts.
acbuild
GONZO Lash Up.
I thought about getting a new or used TCI unit
@jpdevol sent me links for a new & used TCI box.
The new one was $924.00! The used one $500.00, with no guarantee.
Following the advice of a few members here I decided to try a GONZO in place of my TCI igniter unit.
I ordered a GN250 Suzuki (Gonzo) box from a London dealer at great expense (£12.69...!) Thinking it would arrive within a few days.
Two week later it has arrived; I could have got one quicker from China, and even cheaper including postage!!
The above will replace the original TCI which I think may be faulty:
I will send this off to a guy that can refurbish it at reasonable cost.
Thanks to @nighthog for the contact.
So I checked out the various threads on the forum regarding this install.
I also checked out @Jim with his YouTube videos which were encouraging.
I bought some six pin dis-connect blocks from Halfords (Bloody rip off @ $6.69 each!).
And proceeded to make a 'pig-tail' to connect the wire loom with the Gonzo Box.
Using this diagram from the forum
As my bike loom is non-standard I worked back from the loom disconnect block to sort the wiring.
Following wire colours actually on the bike in relation to pin location.
My bikes wires do not fully correspond with any wiring diagram due to PO custom build.
I have ended up with this coming out of the Gonzo so far; to match up with the Loom connection on the bike.
(As taken from the TCI which was connected and ran OK until the bike warms up).
(The red/white spur wire goes off to the Moto-Gadget M-Unit as before)
What confuses me is the White/Green wire that seems not to be attached in the wiring diagram above?
Its labelled white/green on the loom side and NC (not conected?) on the Gonzo side.
Yet in Jim's video they all seem to be in the block.
I have yet to connect it to the bike and try it. Maybe wait for Jim to respond.
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I thought about getting a new or used TCI unit
@jpdevol sent me links for a new & used TCI box.
The new one was $924.00! The used one $500.00, with no guarantee.
Following the advice of a few members here I decided to try a GONZO in place of my TCI igniter unit.
I ordered a GN250 Suzuki (Gonzo) box from a London dealer at great expense (£12.69...!) Thinking it would arrive within a few days.
Two week later it has arrived; I could have got one quicker from China, and even cheaper including postage!!
The above will replace the original TCI which I think may be faulty:
I will send this off to a guy that can refurbish it at reasonable cost.
Thanks to @nighthog for the contact.
So I checked out the various threads on the forum regarding this install.
I also checked out @Jim with his YouTube videos which were encouraging.
I bought some six pin dis-connect blocks from Halfords (Bloody rip off @ $6.69 each!).
And proceeded to make a 'pig-tail' to connect the wire loom with the Gonzo Box.
Using this diagram from the forum
As my bike loom is non-standard I worked back from the loom disconnect block to sort the wiring.
Following wire colours actually on the bike in relation to pin location.
My bikes wires do not fully correspond with any wiring diagram due to PO custom build.
I have ended up with this coming out of the Gonzo so far; to match up with the Loom connection on the bike.
(As taken from the TCI which was connected and ran OK until the bike warms up).
(The red/white spur wire goes off to the Moto-Gadget M-Unit as before)
What confuses me is the White/Green wire that seems not to be attached in the wiring diagram above?
Its labelled white/green on the loom side and NC (not conected?) on the Gonzo side.
Yet in Jim's video they all seem to be in the block.
I have yet to connect it to the bike and try it. Maybe wait for Jim to respond.
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There's 3 wires from the Tci pickup.... advance, idle and common.
The gonzo only uses the idle and common.
The gonzo only uses the idle and common.
Not read through .. but perhaps some help
The bogging down # 211 and banging can be the weak spark from a Faulty TCI electronic Part
Or a to rich mixture
I would suspect a low Physics into and out of the TCI ---Or charging as first CSF rule cheapest simplest first
It can be heat dependent.
If fex the charging quits out on the road and the battery has something left You can ride on the battery ,At the end one need a soft touch on the throttle .To much the richer mixture is to rich for running and bike dies but increasing gradually and carefully can do it
A faulty Physics into the electronics can upset it .fex transistors has a design range within specs it is supposed to be fed.Going out of that and problems can come and weird strange problems timing and igniting randomly.
Your wiring seems fine but I would do a check on the connectors and ground.
I dont know your setup but one trick is to temporarilty pull separe wires to Ignition Dont leave them there se if it solves it
I would also check the exhaust bolts so nothing is loose
You are into HiFi it is the same there the equipment has a work design point Transistor stages are fed via components
One component out of spec and worse performance Or even damage
The bogging down # 211 and banging can be the weak spark from a Faulty TCI electronic Part
Or a to rich mixture
I would suspect a low Physics into and out of the TCI ---Or charging as first CSF rule cheapest simplest first
It can be heat dependent.
If fex the charging quits out on the road and the battery has something left You can ride on the battery ,At the end one need a soft touch on the throttle .To much the richer mixture is to rich for running and bike dies but increasing gradually and carefully can do it
A faulty Physics into the electronics can upset it .fex transistors has a design range within specs it is supposed to be fed.Going out of that and problems can come and weird strange problems timing and igniting randomly.
Your wiring seems fine but I would do a check on the connectors and ground.
I dont know your setup but one trick is to temporarilty pull separe wires to Ignition Dont leave them there se if it solves it
I would also check the exhaust bolts so nothing is loose
You are into HiFi it is the same there the equipment has a work design point Transistor stages are fed via components
One component out of spec and worse performance Or even damage
Cheers @Jan_P
genius prognosis.
yes my bike runs rich looking at the plugs after a ride.
I will look at this problem from your angle.
yes I like high end HiFi and apply logic to resolve issues there.
I also apply logic to my bike, but I’m far weaker as a mechanic.
Everyone here helps me, so I apply their logic and suggested solution.
This interaction has made my XS650 ownership an addiction / pleasure even with the problems. Thank you all.
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GONZO.....No Go!
OK I wired up the Gonzo pig-tail following my bikes loom as it works with the TCI unit.
This is probably non-standard XS loom positions due to custom build.
I then took the pig-tail wires and transferred them to the pin positions at the GONZO end connector
As suggested in this wiring diagram. I dont have a kill switch; just turn off the ignition key.
Moved to the bike and connected up.
Tried a test fire and baby wont run. Motor turns over but will not fire up.
Below is a side by side of the Gonzo with the TCI:
Red wire spur on Gonzo & brown wire spur on TCI go to M-Unit ignition point.
White / Green to Gonzo is not connected.
What am I missing?
Answers on a Post(card) here please.
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OK I wired up the Gonzo pig-tail following my bikes loom as it works with the TCI unit.
This is probably non-standard XS loom positions due to custom build.
I then took the pig-tail wires and transferred them to the pin positions at the GONZO end connector
As suggested in this wiring diagram. I dont have a kill switch; just turn off the ignition key.
Moved to the bike and connected up.
Tried a test fire and baby wont run. Motor turns over but will not fire up.
Below is a side by side of the Gonzo with the TCI:
Red wire spur on Gonzo & brown wire spur on TCI go to M-Unit ignition point.
White / Green to Gonzo is not connected.
What am I missing?
Answers on a Post(card) here please.
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