Post by: Martin6 on April 11, 2023, 05:25:46 PM
Rather than add to that topic, I thought a new one is in order!
I have some miscellaneous other minor issues to have a crack at and any words of wisom are very welcome:
- Neutral switch needs checking, remains dimly lit when in gear;
- I have a strange tramping sensation through the bars on some roads at speeds over 30mph. I'm hoping it is wheel balancing, as the red dot is not right on the tyre valve, and there is a 20g wheel weight close to the valve, which isn't where I'd expect it? However it may be front suspension. Standing, front brake on and pumping the bars, it moves up and down and seems damped, but is stiff. Will check which fork oil it has in there. What grade is recommended for a compliant ride?
- Difficult to find neutral, easy when rolling to a stop, but not when stationary;
- May be related; the clutch bite seems quite late in the lever outwards movement, but no clutch slip is evident when i open the throttle. Is this usual?
👍
Post by: Bryanj on April 11, 2023, 06:05:36 PM
Lot of debate about the dot on tyres but personaly seen them all over the place with no effect, could need wheel truing or balancing, Honda tolerance for true is 3mm side to side and vertically(mot says 4mm) Sounds like neutral switch is failing and the clutch needs adjusting as per manual.
The full Honda workshop manual is on this site for download either in alladins cave or Ashs dropbox
Post by: Erny on April 11, 2023, 06:50:25 PM
Post by: Martin6 on April 11, 2023, 06:59:06 PM
Yes, if the high bite point is not normal, I'll look to adjust the clutch. I have the downloaded manual and have the Haynes (not too impressed with the Haynes though).
I'll also be changing the front tyre, which will be a good time to check how true the wheel is. 3mm seems quite a lot. Looks like the forks may be the problem if they're not usually stiff. Mine are definitely stiff. The previous owner replaced one stanchion, the left, as it was bent. So I'm now suspicious of the right hand one. I'll check that with the wheel off.
Post by: Bryanj on April 11, 2023, 07:14:07 PM
You can easily get them closer than 3mm, that only the max allowed
Post by: McCabe-Thiele (Ted) on April 11, 2023, 07:26:46 PM
I could not afford to replace the sprockets & chain so I fitted a new chain only & cured it.
Post by: Martin6 on April 11, 2023, 08:25:49 PM
I might be way out here but when I had a tramping sensation on my Suzuki 750 GS it was the chain & chain wheels causing the issue. To many wheelies by previous owner.Ted, was that felt through the handlebars?
I could not afford to replace the sprockets & chain so I fitted a new chain only & cured it.
Post by: McCabe-Thiele (Ted) on April 11, 2023, 09:37:02 PM
I didn't know a much about bikes back then - no internet - but a fellow biker said it sounded like a stretched chain causing the issue.
Checking wheel balance and alignment might be a better starting point.
Post by: Laverdaroo on April 11, 2023, 10:18:47 PM
When Maxxis first came out the fitments for the VFR’s and other touring bikes had an intermittent vibration that only manifested itself at a certain speed which turned out to be a mismould and all were recalled .
Check your balance is cool and wheel bearings. Any point of contact really, you’ll find the issue
Post by: McCabe-Thiele (Ted) on April 11, 2023, 10:46:43 PM
Post by: Martin6 on April 11, 2023, 10:49:56 PM
Rear is new. Avon RR. I rebuilt that wheel, but checked it again today and all seems true.
Front is about 100 miles old, but has been on 4 years, i could have a flatspot from standing.
Post by: paul G on April 12, 2023, 07:41:18 AM
Post by: K2-K6 on April 12, 2023, 08:35:15 AM
Standing, front brake on and pumping the bars, it moves up and down and seems damped, but is stiff. Will check which fork oil it has in there. What grade is recommended for a compliant ride?
- May be related; the clutch bite seems quite late in the lever outwards movement, but no clutch slip is evident when i open the throttle. Is this usual?
👍
Fork oil, many go too heavy with this in my experience, partly promoting some level of hydraulic "locking" in response to pattering Road surface. Effectively tge fork doesn't want to move at the linear rate the road irregularities are kicking the suspension up at and causing a little "bucking" feel to come through the front end.
Reality check though, is to assess current level of existing oil, too high will give less fork response than design intention.
Try using Motul 2.5 grade viscosity fork oil at correct level /quantity to see if it's effective in getting the response you want. It's a very good oil anyway and won't give problem, but some may prefer 5 viscosity.
Healthy clutch engagement is ok fairly far out as it makes sure the clutch fully disengages and promotes no clunk when going to first gear when stationery.
If the clutch is used hard on these, heating up the clutch pack moves the lift mech thrust away from the operating mech, and you'll feel the bite point move in toward the bars in this case. You do have to get them pretty hot to see that, but it doesn't usually make it slip with this arrangement.
Post by: Martin6 on April 12, 2023, 10:15:58 AM
Aren't the dots normally the heavy point on the tyre and usually 180 deg from the valve ?Yellow dots, if you have them, are the lightest point on the tyre. To be mounted where the valve is. Red dots signify the flattest point of the tyre. I don't know why, but I always mount them where the valve is, perhaps on the assumption 'flat' = lighter. The odd thing is my front also had a 20g weight at the valve area.
Post by: Martin6 on April 12, 2023, 10:22:58 AM
👍Standing, front brake on and pumping the bars, it moves up and down and seems damped, but is stiff. Will check which fork oil it has in there. What grade is recommended for a compliant ride?
- May be related; the clutch bite seems quite late in the lever outwards movement, but no clutch slip is evident when i open the throttle. Is this usual?
👍
Fork oil, many go too heavy with this in my experience, partly promoting some level of hydraulic "locking" in response to pattering Road surface. Effectively tge fork doesn't want to move at the linear rate the road irregularities are kicking the suspension up at and causing a little "bucking" feel to come through the front end.
Reality check though, is to assess current level of existing oil, too high will give less fork response than design intention.
Try using Motul 2.5 grade viscosity fork oil at correct level /quantity to see if it's effective in getting the response you want. It's a very good oil anyway and won't give problem, but some may prefer 5 viscosity.
Healthy clutch engagement is ok fairly far out as it makes sure the clutch fully disengages and promotes no clunk when going to first gear when stationery.
If the clutch is used hard on these, heating up the clutch pack moves the lift mech thrust away from the operating mech, and you'll feel the bite point move in toward the bars in this case. You do have to get them pretty hot to see that, but it doesn't usually make it slip with this arrangement.
Post by: Martin6 on April 12, 2023, 04:17:49 PM
The K6 has a later design of fork. It takes 155cc to 165cc of oil, about 50cc less than the original forks. It's not immediately obvious in the Honda or Haynes manuals. I guess it is possible previous maintenance might have been to the original fork oil quantity specified. Would too much fork oil give harsh riding symptoms like this?
I re-checked the rear wheel (I recently re-built) and it still seems true and spokes tensioned. Chain seems OK. It spins nicely without any lateral play in the bearings and the rear brake is smooth. So i think the used, replacement hub is fine. The chain is not in the first flush of youth, but doesn't particularly lift off the rear sprocket. Tension is there-abouts. So, in my mind, I've ruled out rear wheel and chain.
I do notice, when I spin the wheel, a ticking sound from the front sprocket area. A quiet rhythmic ticking, like the old Sturmey Archer bicycle gears, when they freewheel. The sprocket is tight, it's not particularly worn and the chain runs smoothly on it. The shaft the front sprocket is on has a small amount of lateral movement, 1-2mm maybe. The ticking is coming from within the engine cover (inside the gearbox?). Is this all normal? If so, I'll concentrate on the front forks.
Thanks, Martin
Post by: Oddjob on April 12, 2023, 04:45:48 PM
I'm a little concerned about the lateral movement on the final driven shaft. In theory there shouldn't be any, the shaft is pressed onto the large sprocket bearing behind the oil seal there, that's normally locked into the crankcase with what's called a setring, this locates in a groove inside the crankcase and so in theory the shaft isn't able to move laterally. Are you pulling the shaft or the sprocket?
The front sprocket can cause some problems if you buy cheap, it's essentially a castellated hole that slides onto the drive shaft, this is then locked in place by a fixing plate, that locates, spins 90 degrees and bolts onto the sprocket. If the sprocket is a cheap make it's been known for the castellations to deform, so that the sprocket moves on the shaft forwards and backwards, better make sprockets use harder metal and they tend not to do this for much much longer, by the time they do the teeth are buggered anyway. Check the fixing plate for wear marks, if that's worn it will allow the sprocket some lateral movement, the sprocket shouldn't be rigid, it has to have a small amount of freeplay to adjust to the drive chain angle as it lashes about but it shouldn't be a great deal. Is the front sprocket maker marked?
Post by: Martin6 on April 12, 2023, 05:19:03 PM
Getting quicker at taking the cover off!
Post by: Oddjob on April 12, 2023, 05:24:50 PM
Post by: Martin6 on April 12, 2023, 11:10:06 PM
If it is the bearing, there's a seal behind the sprocket and then the bearing. Is this the "final driven shaft" (fig. 5.18 on pg 70 of the factory manual)? It looks like it would need to have the engine case open to replace that bearing?
Post by: Oddjob on April 13, 2023, 01:29:52 AM
Post by: Johnny4428 on April 13, 2023, 09:36:25 AM
Post by: Martin6 on April 13, 2023, 09:48:51 AM
So, I am relieved. I can’t afford a strip down at the moment. I want a season to ride the bike, find any more issues and then, maybe next year is the renovation year, if needed.
A picture of the front sprocket and retaining plate is attached. I will replace these, new chain and tab washer. Rear sprocket looks fine.
On a 1976 made K6, is it a 520 or 530 chain, I think it's a 520? 102 links? Can't find it in the Honda manual.
Post by: Bryanj on April 13, 2023, 09:55:22 AM
Post by: McCabe-Thiele (Ted) on April 13, 2023, 10:22:30 AM
Post by: Martin6 on April 13, 2023, 10:23:20 AM
That sprocket is definately worn out, put up a pic of the rear wheel sprocket before you buy any thing as a kit can be cheaperPicture attached. Where would you recommend for decent quality chain and sprocket sets?
Post by: Bryanj on April 13, 2023, 12:07:16 PM
Visualy looks like 530 to me which is the old British 5/8x3/8 so try measuring between pins and width of roller, i also thought all the 620 front sprockets were held on with a central bolt but its been over 40yrs since i did one so no guarantee.
You could try looking up the parts for your bike at cmsnl it should tell you there.
Post by: Bryanj on April 13, 2023, 12:08:49 PM
Further to that you need to trawl through all the pages as you will find the same things at different prices on different pages, also do oil and ail filters, plugs,etc
Post by: Martin6 on April 13, 2023, 12:23:19 PM
I'll search online to get the sprockets.
👍
Post by: Bryanj on April 13, 2023, 12:56:39 PM
Post by: Martin6 on April 13, 2023, 03:11:11 PM
Post by: Bryanj on April 13, 2023, 04:42:59 PM
Post by: Martin6 on April 13, 2023, 05:29:55 PM
They had some other stuff I was tempted with, but I'm holding off cosmetic upgrades this year. That's a too long list! I want to try to get it reliable before I go down that rabbit hole.
Martin
Post by: flatfour on April 15, 2023, 10:37:22 AM
The effect when riding with the wider chain was certainly odd, as though something was speeding up and slowing down in waves, felt through the whole bike.
Post by: Martin6 on April 16, 2023, 08:22:20 AM
Post by: McCabe-Thiele (Ted) on April 16, 2023, 09:43:39 AM
Is the wheel rim & tyre completely round - try some visual checks with the front end jacked up - rotate wheel check against best means you have of looking for ovality.
Fork oil change you already have in mind.
I've no experience of effects of wheel bearing wear aside from noise - the front brake will make wear difficult to check.
Probably stating the obvious so just trying to give you my thoughts.
Post by: Martin6 on April 17, 2023, 05:17:16 PM
Post by: Nurse Julie on April 17, 2023, 06:26:50 PM
Post by: Martin6 on April 17, 2023, 11:00:58 PM
I decided to change the fork oil this evening:
The left fork had 200ml of oil and it was a little thicker than the 5W30 fork oil I've bought. It had some dark residue in the oil. The right had 160ml of ATF, which was clean. According to the >K4 supplement in the Honda manual, the correct amount for a K6 would be 155-165ml. 5w30, or ATF. So I put 160ml in both. Difficult to be sure, but I feel it is now slightly easier to pump the forks. At 200ml, perhaps the left fork was hydro-locking on poorer surfaces? On the other hand, 40ml isn’t much, so probably not.
I have a longer ride planned tomorrow, to go and see a friend's dismantled Suzuki GT185. 30 miles each way. A good chance to see if the oil change has made any difference.
Post by: Bryanj on April 17, 2023, 11:30:30 PM
Post by: K2-K6 on April 18, 2023, 09:24:10 AM
As Bryan noted, its quite a big shift in air volume as it changes much more in ratio through the travel when you start with less space above the oil. Effectively it's making a more concentrated ramp up in spring rate from the resulting air chamber being decreased in size.
One of the reasons I favour a dedicated fork oil like Motul is because it can be more optimum in regard to stiction which is prominent in sliding bearings. ATF is a good balance, but very tighly controlled for it's finite friction properties to ensure consistency in the auto transmission clutch packs, has good anti foam properties too. Dedicated fork oils don't need that friction consideration and generally outperform in that regard. It does make even an old fork perform the best I've found when used.
Post by: Martin6 on April 18, 2023, 06:20:34 PM
Also, the throttle has started hanging open again. I think that's the damage to the slide/bore on carb no.4. This bike is fighting me. :)
Post by: Oddjob on April 18, 2023, 07:13:56 PM
Post by: Martin6 on April 18, 2023, 10:39:26 PM
How are you all lifting the front end off the ground? I don't have a bike lift. At the moment, I'm putting a block of wood on a car hydraulic jack, bike on centre stand and lifting with the jack under the sump. Is the sump strong enough? It feels a bit hairy and I'm unable to strap the bike to anything. On my Norton I can easily weigh the back of the bike down, which lifts the front just clear of the ground. The C of G on the Honda doesn't allow that.
Post by: Laverdaroo on April 18, 2023, 11:18:26 PM
Bit of a cowboy ‘get out of jail free’ card but it works
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Post by: Oddjob on April 19, 2023, 12:44:22 AM
Post by: Laverdaroo on April 19, 2023, 12:46:01 AM
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Post by: philward on April 19, 2023, 03:44:36 PM
Interesting to hear outcome with forks, hopefully positive.
As Bryan noted, its quite a big shift in air volume as it changes much more in ratio through the travel when you start with less space above the oil. Effectively it's making a more concentrated ramp up in spring rate from the resulting air chamber being decreased in size.
One of the reasons I favour a dedicated fork oil like Motul is because it can be more optimum in regard to stiction which is prominent in sliding bearings. ATF is a good balance, but very tighly controlled for it's finite friction properties to ensure consistency in the auto transmission clutch packs, has good anti foam properties too. Dedicated fork oils don't need that friction consideration and generally outperform in that regard. It does make even an old fork perform the best I've found when used.
I wasn't happy with the fork action (picked up all the little undulations) on my 500 and following asking about suggested improvement, Nigel (K-K6) suggested a thinner Motul fully synthetic 2.5w fork oil and there a great marked improvement in normal riding - bearing in mind I'm not a footrest scraper anymore!
Post by: Martin6 on April 19, 2023, 04:33:44 PM
I would appreciate some advice on the top steering bearings. It swings fine, left to right. Just wonder if the top housing in the photo is correct. It has a 6mm recessed section showing below the bearing cap. It looks odd, is that the way it is meant to look? Can't see a photo in the manual.
I'm still working out the safest way to lift the front wheel off the ground!
In the meantime I've checked the carbs again. Two of them were pretty stiff and scoring the slide cylinder. I bit the bullet and worked on the scuffed areas with emery cloth. Required a few attempts, but now they slide reasonably smoothly. Be interesting to see if I've ruined the vacuum. No choice really, the throttle was sticking open. :(
Post by: McCabe-Thiele (Ted) on April 19, 2023, 05:10:04 PM
Other makes & prices are available.
.https://www.ebay.co.uk/itm/203603502986
Post by: Martin6 on April 19, 2023, 06:43:29 PM
I like that solution. Wide enough to give some stability. Ordered.
I did think about carving frame shaped grooves in a 4'x2', but it would still be unstable on my jack.
Post by: McCabe-Thiele (Ted) on April 19, 2023, 06:58:30 PM
The listing photo is a bit misleading as it shows a bike with both wheels off the ground - that looks iffy to me - I strap the rear wheel down whilst on the center stand then use the scissor jack.
Post by: Martin6 on April 20, 2023, 03:54:27 PM
Front wheel check will be at the weekend, after delivery of my new bike jack. I noticed some muck in the left hand fork oil, when I drained it. I'm wondering if there may just be an accumulation of crud that side, which affects the damping action? Has anyone ever flushed a fork out to clean it, without dismantling it, is that possible?
👍 Martin
Post by: Laverdaroo on April 20, 2023, 04:14:17 PM
ble to get all the crap out properly.
Post by: Martin6 on April 20, 2023, 04:23:44 PM
Post by: Laverdaroo on April 20, 2023, 04:29:21 PM
Post by: Oddjob on April 20, 2023, 04:35:08 PM
If you remove the forks entirely, loosen off the bottom bolt first, whilst the fork tubes are firmly clamped by the yokes, same for the top nut, loosen off or you'll struggle getting it loose afterwards.
Post by: Martin6 on April 20, 2023, 06:39:41 PM
Post by: nobber1 on May 08, 2023, 02:45:19 PM
Post by: Martin6 on May 08, 2023, 05:54:47 PM
I am very puzzled by this. I even suspected a slight weave and wobble at the front. I re-seated the tyre, then replaced it. The wheel is true and so is the new tyre.
I still have an irregular lumpiness through the bars. Not vibration. It's like I'm constantly running over compacted mud, until I get to 55/60mph. It doesn't seem related to engine revs.
Post by: McCabe-Thiele (Ted) on May 08, 2023, 07:50:28 PM
Post by: Oddjob on May 08, 2023, 10:37:41 PM
The Hondas these days have the headstock bearings pre-tensioned when you fit them, torque the headstock adjuster ring down to 18lbs, move the headstock a few times to seat the bearings, release the pressure then re-torque to 18lbs, you then fit the top yoke and get a spring balance and hook it to the top yoke, it should take approx 2.2-3.3 ftlbs to get the top yoke to move from central, by hand this feels quite stiff if I'm honest but when the forks/wheel goes in the bars move quite freely. Most people think it's too tight and slacken off the headstock bearings but that then leaves them too loose when everything is fitted.
Post by: McCabe-Thiele (Ted) on May 08, 2023, 10:44:37 PM
Post by: Oddjob on May 08, 2023, 10:48:39 PM
You also need a kit with the spacer included.
Somewhere there is a thread with all the info needed, including bearing sizes.
Post by: McCabe-Thiele (Ted) on May 08, 2023, 11:09:52 PM
I shimmed mine to fit leaving sufficient top thread on my 500. The 400 has only half a kit from a different supplier I will remedy that in the future.
I want to keep the 400 as a runner until the 500 is completed - then I will return to tweaking a few bits on the 400 before I sell her or hit my expiry date - I was 75 at the weekend. lol
Post by: Oddjob on May 08, 2023, 11:14:37 PM
Post by: Laverdaroo on May 09, 2023, 09:59:48 AM
Mine were NTN iirc I did post when I bought a kit for my 400. They also provide a better seal attached to a shim.You don’t look a day over 73 Ted
I shimmed mine to fit leaving sufficient top thread on my 500. The 400 has only half a kit from a different supplier I will remedy that in the future.
I want to keep the 400 as a runner until the 500 is completed - then I will return to tweaking a few bits on the 400 before I sell her or hit my expiry date - I was 75 at the weekend. lol
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Post by: McCabe-Thiele (Ted) on May 09, 2023, 10:02:06 AM
Post by: Laverdaroo on May 09, 2023, 10:02:57 AM
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Post by: Johnny4428 on May 09, 2023, 10:07:21 AM
Post by: Bryanj on May 09, 2023, 11:37:50 AM
Post by: Johnny4428 on May 09, 2023, 12:09:54 PM
Brufen is bad for the waistline mate, i use co codamol!😳😳 I’m lucky! That’s one thing I haven’t had to be concerned about. Co codamol? Haven’t tried it.
Post by: McCabe-Thiele (Ted) on May 09, 2023, 12:36:37 PM
Greatest help to get me riding my bike is nice warm weather - the sunshine lifts my mood plus lubricates my joints somehow.
Post by: Bryanj on May 09, 2023, 05:01:28 PM
Co codamol is a mix of codine and paracecamol, normal ratio 8/500, i have been known to use 27/500!
Post by: Laverdaroo on May 09, 2023, 05:18:32 PM
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Post by: Johnny4428 on May 09, 2023, 09:26:49 PM
It’s like ‘Painkillers Anonymous’ on here today!🤣🤣 analgesics is a major part of us more mature riders.
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Post by: McCabe-Thiele (Ted) on May 09, 2023, 09:38:05 PM
.
Post by: Bryanj on May 09, 2023, 10:14:43 PM
Post by: Laverdaroo on May 10, 2023, 02:18:09 AM
We’re a right bunch of creaky old buggers, love it
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Post by: Johnny4428 on May 10, 2023, 07:25:43 AM
Oh for me it's Betta Blockers , Calcium Channel Whatsits & Protein Pump Inhibitors plus another that made me sprout a pair of decent Man Boobs not to mention the other three.🤫🤫🤫🤣🤣🤣 if it wasn’t serious we could laugh! Maybe we need another section on this forum? Nooooo 🤭🤭
.
Post by: Martin6 on May 10, 2023, 10:55:07 AM
If the bearings were ever notchy they'll still be notchy but as you've loosened them off the whole of the front end will now be moving instead. Fit taper rollers is my advice.
The Hondas these days have the headstock bearings pre-tensioned when you fit them, torque the headstock adjuster ring down to 18lbs, move the headstock a few times to seat the bearings, release the pressure then re-torque to 18lbs, you then fit the top yoke and get a spring balance and hook it to the top yoke, it should take approx 2.2-3.3 ftlbs to get the top yoke to move from central, by hand this feels quite stiff if I'm honest but when the forks/wheel goes in the bars move quite freely. Most people think it's too tight and slacken off the headstock bearings but that then leaves them too loose when everything is fitted.
Can you recommend a taper bearings set? Are they simple to fit, without any machining and decent instructions?
Thanks.
Post by: McCabe-Thiele (Ted) on May 10, 2023, 02:54:08 PM
Good quality make bearings at a sensible price - I would measure the height of your old bottom bearing plus any shims then check against the bottom bearing in the kit use the bottom seal & any shims in the kit to ensure you get the bottom height correct.