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Discussion Starter #1
I have this 96 Trident engine I just picked up from a s***** yard. The 3rd cylinder exaust exit hole has oil around it and in it. The spark plug for the 3rd cylinder also has oil on it. What should I be looking for and what should I replace???????????? :(
 

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Since you can't run a proper compression test, you are a bit stuck. Normally you can run a compression test (engine running), then run a dry and a wet leak down test. Maybe you can still run a leak down test. You can look at a repair manaul (the better ones will have a good description of what to do, but you can also look around the web) for informaiton on the specification.

In a nutshell, you turn the engine over until it has a peak compression (peak pressure), then you stop turning the engine over and leave the compression tester on the cylinder, noting the time. You come back and check the gauge at the time in your spec sheet and note the pressure loss from when you started. Do that for all three cylinders. Now you have some clues to what may be happening, such as a leaky head gasket or bad valves (which should show up as a high loss on both tests). If your wet test has a higher peak pressure, and has a lower leak down loss, then you have a likelyhood of a worn cylinder or bad piston.

If you were to pull the head, and open/remove the valves you could look at the back of the valves. If you have bad valve guides/seals you will see a lot of crusty-wet-oily black stuff on them. If you have a single bad cylinder this should be fairly obvious. Usually you will only see this on the intake valves as they don't get as hot as the exhaust, since air/fuel is cool on the intakes, and there is vacuum on the intake, including any leaks around the valve to guide space. There is more pressure on the exhaust air stream which tends to blow up through the valve stem to guide space versus the pressure direction of the intake.

All guides leak a bit, and all cylinders leak a bit, especially on a used engine, but you are looking more for a smoking gun. Hopefully you got this engine cheap and don't mind figuring this out. Worst case, clean it up, adjust the valves (if needed), stick it in your ride and see how she runs. Just don't put your tools away until you've had a chance to test it. Especially as winter is on its way. Maybe you can real quick install it and do a compression and leak down test. The tool isn't particularly expensive, and may be rentable at an auto parts shop.

Remember, it's the differences that are usually what is important, not the absolutes (that only counts in thermonuclear devices, MotoGP, and a new motor you paid big money on).

I am sure others can add some details & corrections here.
 

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Discussion Starter #3
Hi Douglas

Thanks for your advice. You seem to know much more than I about these motors. After having carefully looked at the Triumph service manual I noticed a difference between the Trident and the Tiger engine. This is from the service manual.
Cylinder Head
valve lift (In) on the Tiger is 7.1mm and 8.9mm on the Trident
valve Lift (Ex) on the Tiger is 7.0mm and 8.6mm on the Trident
all the rest of the info is the same.
My question is as follows . Can I take the top engine head of the Tiger with its valves and use it on the Trident engine. The reason is the broken engine mount on the Trident engine, I need to replace it. The other reason is the exaust ports on the Tigers head are nice and clean, no oil leak.
What does valve lift (In) and valve Lift (Ex) mean can I swap engine heads between these two motors???
Thanks ...
 

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I ought to reference your 'oil' on the head. If it looks like it just leaked, versus is a burned on/crusty look, then it may have been from the angle it was sitting at when it was stripped. I don;t have any internal experience with these engines, just a lot of old experience with old (cheap) cars and motorcycles over the years.

The lift/duration/etc numbers are because different models of this engine have different cams, with (reported) the high performance models having forged crankshafts, also improved quality rods, higher compression pistons, and different ignition systems (higher rpm limiters).

Just like Chevy did with 350" engines in a Camaro versus a Corvette, versus a pick up. All tuned a bit different for the application (and dollars spent).

Since you need to swap the heads anyhow, oil isn't any issue. You will want to pay special attention to any hints in the manual(s) on the cam chain, as that may be the biggest pain. I would check the valve clearances, remove the various cams, swap shims as necessary, then recheck them all prior to installing the cam chain (if you can turn the cams). It ought to be easier than using the shim tool. At least in theory this sounds easier, and can be done on the bench. A good reference manual should tell you how to measure the cam chain for stretch, which will probably be in spec.

A machine shop I used years ago verified good valve seating by tilting the head up so that the ports could be filled with solvent and looked to see if anything leaked around the valves. Told me he wasn't going to make any money off me that day. That is with the cams out (no lifted valves).

This might be a good time to change the vlave guide seals. You can access them with the cam out. You can either buy a valve removal tool, or maybe even rent one at an auto parts store. Even ask you dealers service dept how much to change them on a carry in head. It is fairly easy to do. These seals reduce the oil that can get in around the valve stems ( alittle will always get in there -- very little, for lubrication).

This is a great opportunity to see how your ride ticks. While you have the engine out and apart, look up the 'starter sprag clutch' threads around here.

Also, compare the alternators to ensure they are the same wiring wise (swap as needed). As well the ignitor and timing rotors. Bikebandit.com has online parts listings by model. Open two browsers and compare pics & part numbers to see.

I don't know about Tiger's or Trident's, but presume they will be similar to Tbirds, etc. There are old style and later style carbs (Mikuni and Keihin) as well as the early and late intake manifolds (the old ones had a nipple in the middle of the airway -- bad). All information in the Classics forum, presumably similar info is available in the Trident and in the TIger forums.

That's the good part about this time of year -- lots of winter to get it right and no (or much) riding time affected. Get yourself a good small (1/4" drive) torque wrench. Stuff the cam chain valley with clean rags (one 'oops' will become a crisis as you hear the nut rattling down the cam chain valley) while assembling the head.

Have fun, this is Zen and the art of motorcycle maintenance.
 

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Hi guys, thought I would add a little to the 'leak down' testing for interest.
I use a Motion pro tester for leakdown tests almost daily.
The guage reads in percentage of loss.
The leakdown test MUST be done on a cold engine, with a filtered/trapped air supply to prevent moisture being forced into the cylinder.Compression test on a hot engine.
With the cylinder concerned at TDC compression,in gear,brake on to prevent rotation, apply and zero the guage. The ideal reading is 6-10%. No 'timing' of the leak is required.
With the 70psi pressure applied to the cylinder, put a piece of tubing to your ear. Listen to the exhaust ports, inlet ports,crankcase breather outlet and adjacent cylinder via the spark plug holes.Finally remove the radiator cap and look for bubbles.
You can judge the amount of leakage by listening.
EXAMPLE:Lets say you have a test of 8%.
You note some leaking from the breather, no leaking from the exhaust and a hint of leak at the inlet.
Result: the rings slightly worn (will always be a degree of leak,even new with meticulous assembly).
The exhaust valves are good. One or both of the inlet valves for that cylinder are leaking. May be a tight clearance there or pitting on the valve seating.
At only 8% I would look at the clearances.
After making the required adjustments I then note another leak test. At the next service I again do a leak test to monitor that cylinder. In most cases the 'sealing' of the engine improves.
Mojoinco is not quite correct when saying the actual reading doesn't matter as long as they are close to each other.Any reading in leakdown over 15% requires investigation. If a engine comes back with uniform low compression readings, it needs work.
On your Tiger/Trident engines I would expect to see 160-180psi and all within 5psi of each other. Both engines run the same compression ratio.
As for the ignition, the Tiger engine advances 3degrees more at 6500rpm. You can quite happily run your current igniter and rotor. The trident rev limit comes in at 9700rpm, the Tiger igniter 8750rpm. No changes required unless you want to up the limit to take advantage of the extra oomph.
The head on the Tiger will go straight to the Trident.
Cam chain etc the same.
A quick guide to cam chain condition can be achieved by counting the teeth on the tensioner ratchet with the chain tensioned. Tensioners without a damper pad should not extend more than 12-13 teeth, 8-9 teeth if a damper is fitted to the plunger. With the cam chain wedged, remove the 19mm nut securing the cam chain tensioner spring. Then carefully remove the tensioner body and count the exposed teeth on th plunger.
If you have difficulty getting the valve timing spot on with the mark on the rotor and the marks on the sprocket this also indicates a worn chain.
Cam journal diameters on both engines are the same,so a cam swap to improve the perfomance of the Tiger is quite feasable. The increased lift and duration will also mean some jet,needle and pilot adjustment.
Mojoinco mentioned the inlet rubbers, he is correct in suggesting a change from the 'nippled' manifold. The replacement is part number ZT1240080 about $8 US
Did you get the gear change sorted Bluetiger?
cheers,
Kerry
 

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Discussion Starter #6
Hello Mr. Daytona & Mr. Mojoinco

Just to tell you exactly where I’m at. I will try to explain what was done so far, so you could get a feel for what I will attempt to do. If I only knew what I was getting into when I first bought the Tiger I would have had second thoughts. Remember I never took an engine apart. The Tiger was bought as a project to repair over the winter, I never thought I would have to take the entire thing apart. You should see my garage its amazing how many parts are in an engine.
The Trident engine was bought on EBay and shipped from Ohio to New York and then was picked up by me from New York to Canada.
Both these engines are on the bench. The Tiger engine is completely apart and the Trident engine is still in one piece but on the bench without the radiator and not yet on the bike. The reason being an oil leak from one of the exhaust ports with a burned on/crusty look & a broken engine mount on the head.
I have so far removed the spark plugs on the Trident engine. I do not have a leak down tester but I do have a good compressor. So, I took a spark plug apart and attached my compressor to it and put it back in the bad cylinder to try and figure where the leak is coming from. TDC, top dead center. Thank God for the internet. Once the cylinder at TDC I turned on the compressor but air was escaping from the exhaust port and not just a small leak, more like rushing air. I then thought my valves are not completely closed so I turned the sprocket with a large wrench and did a complete cycle to figure out that air is escaping from the exhaust valves even when the valves are closed at their max. Maybe the valve heads need cleaning? What will a leak down tester do more than what I have already done with just my compressor? Must the ngine be on the bike to do a leak down test? I still do not know if the oil leak is from down below (cylinder) or from above the valve stem or valve guide.
I know I must replace the head due to a broken engine mount on the Trident engine.
I went through the service manual spec sheet like Mojo suggested for both the Tiger and Trident engines. I noticed on the service manual that 2 different timings were made for the Trident engine one giving 98ps and the other giving 85ps. The Tigers timing that matches the Tridents timing is the timing with 85ps. My question is what timing does this Trident engine have, timing 1 with 98ps or timing2 with 85ps. How can I tell and if it’s a 98ps engine can I still swap the head from the Tiger to the Trident?
The camchain tensioner spring free length is the same for both that is 73.3mm. Everything else the same, except for what I mentioned earlier in my last email valve lift.

I really want this to work and I don’t want to rush and foul up, so whatever details you give me are read with great attention and thought. Example you mentioned the inlet rubbers and part number ZT1240080. I am assuming inlet rubbers have something to do with the carburetors, so I went to the bikebandit.com site like Mojo mentioned and could not find inlet rubbers nor part number ZT1240080.
Oh &, for Daytona, the gear change is the least of my worries right now.

Hoping to hear from you again. Thanks a million and hope I did not bore the lights out of you both with this last post….
 
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Way out of my depth here on most of this stuff, but if you're looking for the part on Bike Bandit's site try 1240080T0301.

HTH,
-Kit
 

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Good Luck with that......

[ This message was edited by: Mossy21 on 2006-12-02 21:23 ]
 
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Strange. Here's what I get from Bike Bandit:

Search Term: 1240080T0301 1 Result
Part Number Name Your Price
1240080T0301 RUBBER, CARB TO HEAD $8.76

Cheers,
-Kit
 

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Carb boots: Look under 'cylinder head & valves'.

When in bikebandit, do a search for the TIger and Trident's (may be different serial number ranges within a model) and see if the igniters are different. By looking your igniter over you may see different part numbers or even different wiring as clues.

Deferring to 93-Daytona, the exhaust valve(s) are not closing, or more accurately, they are not sealing. As Daytona noted, check your exhaust valve clearances (the feeler gage should have at least a bit of lubrication/oil -- not done dry). If this is in spec, you likely have a burned or stuck valve or even a cracked valve seat. If it is not in spec, turn the engine over and verify it is at TDC, as well that there is no carbon stuck in the seat (the pressure leaking out as you raise the valve out to help dislodge it. Not real important as you are going to be changing the head (but a great opportunity to troubleshoot and not hurt anything that matters).

Other than the commitment to carb tuning, I would certainly consider Daytona's suggestion to use the Trident cams. You may wish to use your Tiger cams to get things running, then consider the Trident cams afterwards. You could consider the Trident cams with intake (filter and airbox) modifications, and also if you change the exhaust, as you will see more effects (and you will be modifying the carbs anyhow).

Daytona, are both the total advance and the rev limiter controlled by the igniter, or is there a different advancer/igniter/ wheel assembly so that one can take the high total advance mechanism & the higher rev limiter igniter and assemble them? Also, I thought there is generally a time associated with the leak down test (5 minutes or something like that)?

Here are a couple of pages I found of interest on the leak down test. Other than the implied math (setting the intake air pressure to 100 psi, then using the reading as a direct percentage: 85 psi meaning 85 % for a 15% leakage) they seem to be simple enough. I think that it would be easy enough to re-use a compression gage (or at least the hose from one) to build a leak down tester.
http://www.xs11.com/tips/misc/misc3.shtml
http://en.wikipedia.org/wiki/Leak-down_tester

Keep in mind that Sears (Roebucks in Can?) is having a lot of specials on tools and sets pre-Christmas, so identifying your needs now will save some $$ later, toolwise.
 
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