Triumphrat

Tommybro · 06-27-2008, 11:34 AM

I have a simple question and one concern. Ever since I purchased my used '97 Sprint a few months agoI have had the fuel tap knob pointing down. I just got the bike back from the shop for a tune up and major look over. The tech told me I had the fuel tap in the reserve position. The paint has worn off on the tap and after looking at the owners manual he is right.

So everyone has the knob pointing the the rear of the bike, arrow to arrow? This is the 'On" position?

Now to the engine rattle noise. The tech was concerned with the "louder than usual" engine noise below 2000 RPM. He mentioned the well know clutch sprag horrors. But he didn't say anything about the alternator bolt problem that happens once in a while. From what I've read on this forum I have the symptoms of that. My '99 Legend was a rattle bike at idle and this one doesn't sound that much different. From what the tech at the Triumph shop says is making me a little paranoid. Happy summer!

ervdrvr1 · 06-27-2008, 12:24 PM

Tommy,
Yep, up is Prime, rear is On, and down is Res. Does the fuel tap knob rotate all the way around? If so, buy a new one(appx $10) and fill the voids on the back side with epoxy to prevent breakage. If not, pull it off and check, if not filled, go ahead and fill it before it does break. As for the rattle, only way to know for sure if it's the alt is to pull if off to see if the bolt is broken. Earlier engines have a bolt on each end of the drive shaft securing the drive gear and alt shock absorber housing. Later engines have a single bolt thru the shaft with a nut on the other end securing the gear and shock housing. Not sure what year/VIN# this started. Half to pull the clutch to gain access to the inside end. The thru bolt is supposed to correct the problem of sheared bolts, but may shear anyways. Your model should have the updated starter clutch, so that may not be the prob.
Also, how long has it been since last valve lash check? Also, check the spring for the cam chain adjuster(untensioned length 73.7mm/2.9in). If too short, replace. Also check the cam chain tensioner guids/blades.

Someone else chime in if I missed something, or got something wrong.

Erv
Deep in the Heart of Texas!!

Tommybro · 06-27-2008, 01:44 PM

Great all straight with the fuel tap.

I just had it in for a major look over/tune up. He said the valves were and carbs were in spec. The plugs were pretty black, and they installed hotter plugs. All questionable fuel lines were replaced. Compression was about 10lbs. less in the #3 cylinder. Hmm.

I submitted my vin# a while back and someone said I should be OK with the clutch sprag thing.

Hell, I'm just going to ride the **** thing.

T.

daytona 750 · 06-28-2008, 04:03 AM

i dont want to scare you or anything, but my local dealership mentioned these things when i had a rattle/knocking,when i got it home and stripped it, it was actually a big end bearing had destroyed itself!
i can find no reason for it to have gone, apart from a load of metal in the sump from the shattered sprag clutch
(the first heavy duty one lasted 3 days)
basicly, the engine hadnt been flushed through properly afterwards, and i think it picked up abit of metal between the crank and big end bearing which reduced the play and caused it to over heat, melting the bearing shell.the upper one had actually been squeezed out so hard, it was pushed up the sides of the conrod!

Roden · 06-28-2008, 07:50 AM

Listen carefully for a distinct rattle around the alternator area.
If you hear a rattle that diminishes or disappears when you turn on the headlight, then it will be the alternator rotor bolt has either loosened or sheared off.

Not hard to fix but first have a listen and let us know.

Cheers,

Roden

Tommybro · 06-28-2008, 10:53 PM

My headlight(s) come on automatically so I can't do the on/off alternator test. I went for a ride this morning. Before I left the house I knelt down and put my ear on the motor at different spots. The loudest knocking seemed to be coming from the crank area. There is so much going on I really couldn't tell what's normal and what's not a normal sound with these engines. Sure is silky smooth going through the gears though.

Another new issue reared it's head today. After riding 30 minutes or so, I would leave from a stoplight and the motor cuts out and in. After the RPMs are up and going down the road, no problems. Now I nervously anticipate this huck-a-bucking every time I take off from a stop. Not only embarrassing but very dangerous.

I had coil failure on my Legend, but if I remember it would seem to loose power, not cut in and out. I replaced them with Nologys and the bike ran flawlessly until the day I sold it.

tritonwow · 06-29-2008, 04:25 AM

I had a god awful noise and after tracing the obvious decided I had to crack the lower end to see if the sprag was done for. The noise ended up being deteriorated balancer cush rubbers (on both since I have a D1200). I could never really pinpoint the noise while the bike was together and running. Looking at the lower end, and other than a million bits of rubber in the pan, I didn't see any noticeable wear in the balancers. My guess is I could have run it for quite sometime ignoring the clank and nothing would have happened. Then again the balancer could have finally cracked and shattered and I'd be crying crocodile tears.
Hope you find it.

phil the greek · 01-31-2010, 07:20 PM

Quote:

Originally Posted by ervdrvr1

Tommy,
Yep, up is Prime, rear is On, and down is Res.

My '97 sprint sport has no owner's manual with it - what is PRIME for?

Would I be right in thinking the fuel tap is basically on all the time or is there an OFF setting?

sailfish · 01-31-2010, 07:40 PM

The petcock is vacuum actuated so theoretically fuel should be off if the engine isn't running but it is common for them to stick open. Prime opens the petcock without vacuum so you can get fuel flow without a running engine should you decide that you need that.

born to be mild · 01-31-2010, 07:55 PM

Tommy, your engine cutting out may just be the result of carb icing, anyone concur ?
Phil; Prime is for if youve had the tank off or run out of fuel totally, yes the bike tap is permanently ON, but the flow to the carbs is only actuated when the engine is running, as one of the pipes on the tap is a vacuum pipe which when the engine is turning over opens a diaphragm in the fuel tap and allows the fuel through.
Unless you have a bike like mine with a knackered diaphragm of course, then the fuel is always on, which isnt such a good thing,,,