Fork seals and MOT

[BusterGonads]

I snapped up a nice example of a Honda CB250 Nighthawk the other day for a nice price. It had been on SORN for a number of years. One or two niggles came up - a stuck brake switch now freed off, dead battery, now sorted.

There is a very slight seepage on one of the fork seals if you pump the front end. Just a small smear of oil after thirty full pumps on the front end. One mate of mine - a retired bike mechanic said it might well fix itself as the seal gets warmed up by use. Another said he thought the MOT tester would take no notice of such a little smear on the stanchion from the seal. It makes just perceptible ring at the extent of the maximum compression of the fork.

What do you reckon? Should I put it in for the test or send off for a set of seals and dust shields and do the job before I put the bike in for the test? It would really piss me off if it failed and I wasted thirty notes by chancing my arm. Tight? Yes.

[Riejufixing]

Close-up of the fork stanchion/oily ring?

You'll always have some oil on the metal surface, but it shouldn't leak out. If you clean it up, and then pump your 30 pumps, what does it look like? It could be just a bit of an accumulation under the dust seal. If it's just a perceptible ring & no leaky leaks, I would not worry about it. Check the fluid level, just in case, I think it's often worth changing these normally-neglected components.

IF the stanchion isn't visibly pitted, I'd get it MOT'd. Perhaps, if there's any question, wipe it off "just aroud the corner", but it's hard to know.

If the stanchion is pitted, ofc, you might have to think about replacing it.

[stinkwheel]

I'd pry up the dust seal, pack under it with a sausage of rolled up J-cloth then jam it back down again just before you set off for the MOT...

That trick is as old as fork seals.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Kawasaki Jimbo]

With every bike shop I've ever used you can ask them in advance whether they'd MOT-fail a particular issue and get an honest answer. Ask 'em. I get the idea that it might be leaking slightly due to a lack of use and they might "heal" with use, but still I'd expect to have to renew the seals soon.

[BusterGonads]

Thanks for all of the answers. I have already done stinkwheels trick, but I used kitchen roll swirled up into a sort of paper rope and packed in. This lessened the leakage. I will certainly wipe off any ring as I arrive at the place. They are pretty decent there actually, when I took the CG, the guy failed and re-passed it instantly on headlight aim. He adjusted it for me. They also passed my street twin but it was pretty much brand new with only 6500 miles at that time. There was nowt wrong with it.

Of course it is also right that I should expect to do the job properly.
I already have two bikes, but this came up for £650 ----- a 12000 genuine miles 1997 Nighthawk. Engine is fantastically smooth and works great. I'm more than pleased with the deal I got. Take a look at the photo I took tonight. Can't wait to start using it. I'll drop it off for MOT on Monday if I can be satisfied about the scale of the seepage being acceptable. Wemoto have the seals for £16 made by slinkyglide... Should be ok I hope.

Riejufixing: You ask what the leak looks like. After a two mile ride on a smooth farm track there was a thin ring about as thick as a pubic hair on he affected stanchion at the highest point the stanchion had been forced into the lower leg. The fork has a couple of tiny pits - really small not like I've seen elsewhere. I might try and post a photo of the leg close up tomorrow.

Cheers

[BusterGonads]

[A100man]

[Shaft]

[BusterGonads]

[Shaft]

[Kawasaki Jimbo]

[Shaft]

[BusterGonads]

[Riejufixing]

Oog. Cough mumble furtherseallip damage mumblecough.

Yes, I've heard of these things, but I'm not at all keen on them.

[Minty]

One of my seals started leaking about 2 years ago and one of those jobbies hoiked out some crud and has been fine since. Am fan.
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My fingers smell of your mum.

[BusterGonads]

[Minty]

I'd tell people to copy the design and cut it from a large lemonade type bottle for the same effect.
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My fingers smell of your mum.

[BusterGonads]

[kramdra]

I have changed a few fork seals. Even with oe seals and good stanchions they often weep. While the sealmate tool works at cleaning, it is not enough.

Apply grease under the dust seal. The dust seal will retain it The grease will lubricate, and increase friction enough to allow the oil seal to seal properly.

[BusterGonads]

[Johnnythefox]

My bike has fork gaiters which are fixed in place, I'm told the MOT chap isn't allowed to take them off which seems a surprise.

[BusterGonads]

[King29]

My local bike mot centre is wise to such tricks, they check the back of the fork leg. Worth wiping it off there, run a cloth all over the fork leg and wipe off any residue.

[kramdra]

[BusterGonads]

Passed MOT.

No advisories.

What joy!

Purchase cost £650

Insurance cost £56

Battery cost £25

MOT cost £29

Bike tax £44

Comes out about £800.

Might need a new back tyre. It's a bit skippy on a poor road surface. The Triumph was the same until I changed the rubber. It's definitely the back that is skipping and that tyre is the most worn.

12000 miles, unmolested, engine and bike sweet as a nut. Twenty-two years old, mostly in the garage. What's not to like if you want a cheap runabout?

https://photos.smugmug.com/My-First-Gallery/i-VwC2rmQ/0/d0dd2860/XL/Nighthawk%20at%20Cassies%20-%20Edited%20%281%29-XL.jpg
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2016 Triumph Street Twin; 2000 Honda CG125; 1997 Honda Nighthawk CB250