120 replies to this topic

[Blaqkfox]

Haha yeah theres some videos of doing the barn find tdm on there, but they were awhile back. Havent had a chance to mess with the tdm for a few weeks and I post too much on there lol.

Yeah everything on these carbs is factory fresh. I will have to check where I set the mixture screw, that could be my problem.

I found I could just lift my battery out, still connected, and managed to easily fit a normal sized screw driver in there to balance them. It was actually really easy compared to most syncs Ive done, and Ive probably done hundreds lol

[Blaqkfox]

Ok Im finally back.
I had figured this fuel cut issue was carb related but now Im not so sure. Last I remembered I had trouble with one of the bowls. It kept overflowing. I recall I tested and tested and couldnt find any reason it would. I had modified float height and got it to stop but I thought maybe changing the float height was causing my strange running issue. So I dove back into the carbs

https://i.imgur.com/lz2Owmu.jpeg

Once I had the bowls off I pushed up on the floats to see if float height was drastically off. It wasnt. I thought I had been more aggressive with my float height change, but it was very very slight. One thing I did notice however was the float needle had collapsed in a sense. For whatever reason the plunger part on the once leaky one was unable to support the float under gravity. Here look

This is the left float, the good one that never gave me any trouble
https://i.imgur.com/TU0mlWt.jpeg

And this is the right float, little trouble maker
https://i.imgur.com/Pa62jcq.jpeg

Now the plunger does extend back out, so I guess its just weaker than the other one. Which makes sense. When I was trying to stop the right bowl from overflowing I had tried an old float needle at one point, it wasnt what stopped it from overflowing but once I had solved the problem I just left it in there.

Im now wondering if its causing an issue? I dont know exactly what that little plunger is there to do to be honest.

But Im thinking my issue is elsewhere. I suppose I will check valve clearances next.

What is interesting is the slight knock / hiccup it will do every once in awhile when it idles. Im not sure if this is a cause or a symptom. Is it knocking and thats causing a binding and the running issue or is it a fuel delivery or valve lash issue that is causing the knocking hiccup from that cylinder? Who knows. It did it once while I was balancing the carbs and my vacuum gauge dropped to 0 on the left cylinder when it happened, then shot back up to a regular vacuum reading.

So even though the right carb was troublesome, I think the left cylinder is the one giving me running issues. And the left one is the one I pull vacuum from to power the fuel pump, so I recon Im doing double damage that way. Perhaps Ill change the vac line over to the right intake boot.

The bike seems to run pretty well most of the time, it just seems to have a dead spot around 1/8-1/4 throttle sometimes, not all the time, but if youre just cruising with the throttle slightly open it will feel down on power or feel like a fuel cut, and it does not like when you throttle up quickly, it will bog like a fuel cut every time you quickly twist the throttle, but twist it slow and its fine. Also the random knock / hiccup / backfire through the intake sometimes when idling. Which is all leading me to think valve lash is the likely culprit.

I will try putting the new float needle back in first and make sure the carbs are settled in and then check valve lash I guess.

Edited by Blaqkfox, 17 April 2024 - 06:15 pm.

[Snowbird]

Cam chain tensioner could be slipping a notch and letting the chain go slightly slack briefly.

[Tedious93]

Good catch on the needle dampers. They should return immediately and not hang when depressed. I suspect they are there to keep the needle alive (and the floats as well) under rough conditions that bikes can encounter.

 

You didn't say how many miles are on the bike but looking at the condition the bike was in; it's easy to imagine skipped valve adjustments.

 

I'd check that before anything else.

[Blaqkfox]

Right well I havent mentioned the mileage for good reason lol the speedometer doesnt work so I have no idea if its accurate or not. It stopped at 17,xxx miles. It was missing the cable so I got a new one. I verified it rotates when the bike rolls. So something internal to the gauge is wrong because it still dont work. Someones obviously been in there before too because the needle has been glued back together lmao.

Im currently just trying to find my bag with the new float needle in it. Cant find it anywhere. Id like to rule this out tho so I need to find it

[Blaqkfox]

Ok so new theory, I think this thing needs a clutch, like yesterday. I dont think its a fuel cut. I think the engine knock might be just that, a random knock here and there. But I cobbled the bike together using an old float needle from my buddys cm400 iirc. It was like 1mm too short with the clip on it and that would keep it from seating, so I just took the clip off. Whatever, this is a $1k challenge bike remember, dont judge me.

So after that I rerouted some vac and fuel lines thinking maybe thatd help. It didnt. I ran the bike stationary and everything seemed pretty good. It would still stumble a little with the smallest amount of throttle. I backed the mixture screws out from 2.5 to 3 turns and that seemed to mostly fix that. I think.

Anyways, with the bike seeming to run good I slapped the tank and seat back on and decided to go for my second test ride on it. As soon as I put it in 1st the bike lurched forward and stalled, despite having the lever pulled in. So the clutch plates were yet again stuck. Kinda surprising as I just encountered on the first test ride last month or whenever that was.

So I hold the rpms high and do a little burnout and off I went. Maybe 200 yards I turn into the church parking lot and the clutch seems to be free now. So off I go for a long ride. Working the clutch as I ride to try and get some oil in between those plates. And thats when it dawned on me. This is exactly what the stuttering feels like. Like your dropping the clutch while you ride. As I continue Im noticing that sometimes when I pull the lever my rpms dont increase at all, they should Im still on the throttle and havent let up at all, so the plates are sticking here and there.

I turn around after maybe 5-10 min to head back the other way, clutch seems to work fine coming to and leaving from a stop. And riding seems to be fine now too. Unless unless I pin the throttle in 2nd or 3rd, then when rpms get to about 4-5k itll violently lurch as if im clutch kicking it.

So Im betting its this damn clutch acting a fool and not a fuel cut like I thought. That knocking has sent me on a wild goose chase but I think Im on the right track now. I hope.


Oh also, real quick, are the brakes just shit on these 3VDs? Even my nice one feels spongy and Ive bleed it twice. I chalked it up to the master being weak or something, but then I bought a master for the barn find tdm and Ive bleed it so many times and yet it feels even worse. I mean on my nice on I can pull halfway on the lever before it starts to brake, and on the barn find i have to pull it a good 3/4 of the way or more before it starts to actually do anything. But by the time they both bottom out it stops hard. I thought I bought a new fazer 1000 master cylinder for the barn find one but when it arrived it was used. So maybe both masters are just shit idk.

Edited by Blaqkfox, 20 April 2024 - 10:33 pm.

[dablik]

A common mod is Bluespot brakes and a 14mm MC from an early 900/Fazer/FJR etc.

[fixitsan]

Ok so new theory, I think this thing needs a clutch, like yesterday. I dont think its a fuel cut. I think the engine knock might be just that, a random knock here and there. But I cobbled the bike together using an old float needle from my buddys cm400 iirc. It was like 1mm too short with the clip on it and that would keep it from seating, so I just took the clip off. Whatever, this is a $1k challenge bike remember, dont judge me.

So after that I rerouted some vac and fuel lines thinking maybe thatd help. It didnt. I ran the bike stationary and everything seemed pretty good. It would still stumble a little with the smallest amount of throttle. I backed the mixture screws out from 2.5 to 3 turns and that seemed to mostly fix that. I think.

Anyways, with the bike seeming to run good I slapped the tank and seat back on and decided to go for my second test ride on it. As soon as I put it in 1st the bike lurched forward and stalled, despite having the lever pulled in. So the clutch plates were yet again stuck. Kinda surprising as I just encountered on the first test ride last month or whenever that was.

So I hold the rpms high and do a little burnout and off I went. Maybe 200 yards I turn into the church parking lot and the clutch seems to be free now. So off I go for a long ride. Working the clutch as I ride to try and get some oil in between those plates. And thats when it dawned on me. This is exactly what the stuttering feels like. Like your dropping the clutch while you ride. As I continue Im noticing that sometimes when I pull the lever my rpms dont increase at all, they should Im still on the throttle and havent let up at all, so the plates are sticking here and there.

I turn around after maybe 5-10 min to head back the other way, clutch seems to work fine coming to and leaving from a stop. And riding seems to be fine now too. Unless unless I pin the throttle in 2nd or 3rd, then when rpms get to about 4-5k itll violently lurch as if im clutch kicking it.

So Im betting its this damn clutch acting a fool and not a fuel cut like I thought. That knocking has sent me on a wild goose chase but I think Im on the right track now. I hope.


Oh also, real quick, are the brakes just shit on these 3VDs? Even my nice one feels spongy and Ive bleed it twice. I chalked it up to the master being weak or something, but then I bought a master for the barn find tdm and Ive bleed it so many times and yet it feels even worse. I mean on my nice on I can pull halfway on the lever before it starts to brake, and on the barn find i have to pull it a good 3/4 of the way or more before it starts to actually do anything. But by the time they both bottom out it stops hard. I thought I bought a new fazer 1000 master cylinder for the barn find one but when it arrived it was used. So maybe both masters are just shit idk.

 

If you put your hand on the brake lines down to the calipers, can you feel it swell in your hand when you pull the brake lever (ooer missus !), if so, new brake lines would help

[dapleb]

So something internal to the gauge is wrong because it still dont work. Someones obviously been in there before too because the needle has been glued back together lmao.

Common problem. Clock mech wears. Needle flaps, needle breaks.

[Snowbird]

Silly point maybe (I've been drinking bear with me) does the 3vd have the 1st and 2nd gear thing that limits the torque? Is the gear selector switch shorting and changing timing on you?

[Blaqkfox]

Common problem. Clock mech wears. Needle flaps, needle breaks.

I figured that would be the case. Happens to 80s bmw cars and bikes all the time. Is the tdm gear plastic like bmws? I suppose it doesn’t really matter. If I have extra time I might try and take it apart and print a new one. In case mine is totally destroyed, I don’t recon one of yall know how many teeth it has? And dimensions would be even better, even just a radius.

Silly point maybe (I've been drinking bear with me) does the 3vd have the 1st and 2nd gear thing that limits the torque? Is the gear selector switch shorting and changing timing on you?

I’m not sure what you’re talking about? Can you explain?

[dablik]

Silly point maybe (I've been drinking bear with me) does the 3vd have the 1st and 2nd gear thing that limits the torque? Is the gear selector switch shorting and changing timing on you?

 

If memory serves correctly then no, not applicable to the 3vd, dont ask me how i know (could be wrong, it's been known) but it's stuck in the back of my mind for some reason, there is a conversation somewhere about it..

[Bjørge]

 
If memory serves correctly then no, not applicable to the 3vd, dont ask me how i know (could be wrong, it's been known) but it's stuck in the back of my mind for some reason, there is a conversation somewhere about it..

You're right, the 3VD doesn't have the complete gear indicator switch. There's only one contact point for the neutral.
So - no torque limit in low gears.

[Snowbird]

That's me put in my place, I stand by my drinking excuse....

[dapleb]

Good disclaimer SB. Loike it!

[Blaqkfox]

I think I am going to try just taking the clutch apart first, sanding the clutch plates and cleaning and possibly re-oiling the friction disk.

Still plan on trying to ride it 45 minutes to work tomorrow to change out the tires and chain though.

[Snowbird]

I think I am going to try just taking the clutch apart first, sanding the clutch plates and cleaning and possibly re-oiling the friction disk.
 

How about dropping the friction plates in a pan of hot oil for a while to help it leech out any old sticky oil and absorb fresh as it cools? I have to do this on oilite bushes to remove gumming and re-oil at work on magneto distributor blocks.

[Blaqkfox]

Hmm, I was going to drop the friction disk in oil for 5 hours or so, like you do with new ones, but I hadnt considered using hot oil, thats a good idea. Are you saying to also do that with the metal plates? I know the metals can literally soak up oil over time. I didnt know you can use hot oil to leech it back out tho!

[Blaqkfox]

Really hope this clutch fix works out. Im already slightly over budget on our $1k challenge. Heres the breakdown:

Bike $200
Gas tank $233
Airbox $91.76
Air filter $16.36
Battery tray $20.75
Temp sensor $49.28
Intake boots $13.90
Brake master $54.64
Safety relay $54.30
Chain $43.75
Ignition key set $30
Oil filter housing parts $34.43
Mirrors $30
Fuel pump $51.03
Petcock $92.64
Carb rebuild kit $24.51
Carb jet block $61.95
Idle cable $7
Battery $38.34
*Stator $155
*R/R $70

Total w/o stator & r/r: $1,140.64
Total with: $1,365.64

This does not include: tires, fluids, misc. etc. we decided that stuff would be necessary and negligible for everyone. We also wanted everyone to be on fresh tires and allowed a $200 budget for that, which I failed the budget challenge here as well. The cheapest tires I could find were the Shinko 705s and ran me $233 for the set.

*I have the charging system components but have yet to install them. Trying to keep as close to budget as possible. The bike is charging, just not very strongly. My other tdm will charge 13.5v at idle and up to 14.5v under load. This bike is doing 12.8v idle and fluctuating under load, sometimes as low as 12.9v sometimes as high as 13.5v. I plan to bring the parts with me on the trip incase needed. We have a few trucks following us for the inevitable break downs.

We are running the same rules as the local vintage 500 challenge - you must carry your own gear on your bike: so camping stuff, and whatever else you need. But we are going to let one of the trucks carry the tools, and I think the food?

We will be filming with 360 cams on a few of the bikes and go pros. Possibly a drone also. Weve never filmed a trip like this before so the production /post will be amateurish.

The other participants are riding:
Kawasaki KLX300 (2002[?] decent but crusty, new top end)
Honda CM400 (very clean factory example)
Honda CM400 (hacked up cafe racer turned scrambler)
Honda V65 magna (1980s model, very clean factory example)
Yamaha RT1 (1970s model, this mans is $1600 in this bike rn. It was probably the worst shape out of all of the bikes to start)
Suzuki intruder (if he can get it running in time, he just had a baby)
And of course my TDM.

I think we have some others attending but idk what they will bring. Should be an interesting match up. The v65 was a surprise, I thought I was going to have the biggest CC bike. Atleast the TDM is more suited for the terrain we will encounter.

Edited by Blaqkfox, 26 April 2024 - 03:30 am.

[Catteeclan]

Great idea although I'd struggle to find the time.
Good luck and enjoy to all, looking forward to the vids.