Triumphrat

jeffrey1 · 01-22-2006, 03:08 PM

Now dont everyone blow a fuse,,,, but my concerns are doing all those engine mods and rejet this and drill that to get that little bit extra power is it really worth it? My concern is are we shortening our engine life because as we all know with increased hp comes extra heat and stress and wear ,,,and the weakest link will fail.Has anyone noticed a increase in engine temp after a modification over stock,, with the snorkel removed i noticed a slight raise in engine temp but now it was only slight and even could be the difference in the engine pull and i run it harder ,,, And why i even bring this up is that in the past i have done some 2 stroke snomobile mods ..pipes ,jetting, head gouging , air box mods to get that extra hp and the engine life was shortened by these changes because we run them right to the edge and then a temp change and we would blow a piston or blow a crank.. that is why i have not done any engine changes to my bike except the snorkel removal and the sprocket change honestly iam scared to death that i might screw up a really good working bike and then who can you blame... whooo hoo look in the mirror.. Now this is just my thoughts anyone else feel the same or is it just me???

dazco · 01-22-2006, 04:08 PM

Not at all. First of all, if removing the snorkel made your bike run hotter it's probably only because you added extra air which made it leaner. leaner=hotter. Once you rejet to balance the mixture tho, there should be no difference in heat.

these airbox mods that we all do IMO should have zero effect on longevity because they aren't making the engine work too hard, they're simply allowing it to do what it's capable of which the factory stunted due to regs. Take an old 70's honda twin for example. They ran in a far higher state of tune with higher redlines, compression ratio, longer stroke, and even foam filters. Thats why you'll notice in a few of shorty's posts he's mention his old 70's 450 twin is a bit quicker than his triumph twin thats almost twice the size ! And if that honda was in jeapordy it wouldn't have the 100k miles he's quoted and still be alive and running 35 years later.

Nope, IMO all you are doing is bringing it a BIT out of it's horribly undertuned state to allow it to get a little closer to what it's design is capable of. But nowhere near it's limit. Now if you wanna talk about Bb kits and cams, thats a different story, as you are then modding it way up to where the stresses on the crank for example could end up at or past it's design limits.

bonnieowner · 01-22-2006, 05:17 PM

I agree with dazco that if the jetting is correct the life span of the engine should not be affected. More than one qualified Triumph mechanic has spoken to me about how over built these engines are, so the added power should pose no problem to the crank end of the power train. I think the only real problem would be how the rider responds to the increased power. In other words, if the increased power causes the rider to adapt a new riding style that includes constant reving to the red line, power shifting, and drag type starts, you might expect to see premature clutch problems and possible gearbox related problems. Most people, like me, gas it up every now and then, just to get a feel for the mods we've made. Other than that, we behave ourselves. I feel confident that the mods I've made will not affect long term reliability. Dan

dazco · 01-22-2006, 05:26 PM

Good point...if you ride it the same way as you did pre-mods, it would be no different in how the engine is affected. If you ride it beyond what it was capable of when stock then of course the wear will be slightly more just as it is when you ride a stock bike slow instead of fast. but you're talking slight because the added power you get is relitivly slight.

So in other words, even with s tock bike the easier you are one it the longer it'll last. But the mods in and of themselves won't be any different in longevity.

HiVel · 01-22-2006, 05:39 PM

If you raise the compression, change the cams and increase the valve spring pressure, and perhaps change the timing you will increase wear and if you really run the stock engine hard same deal. Why worry? Those twins are over engineered and are a long way away from rebuilds. Simple jetting and airbox changes should not cause any problems. The two stroke mods you refer to are similar to what I referred to in the four stroke engine-they will increase wear and stress on the mechanism. Get er done!!

CarlS · 01-22-2006, 08:00 PM

Actually, if you make the mods and get the jetting right, your engine should actually run a tad cooler than stock. The engines run on the lean side from the factory. These engines are nearly bullet proof.

LT · 01-22-2006, 08:40 PM

Mine runs a bunch cooler since I richened fuel. When it does wear out, Big bore kit will be part of rebuild.

Shakey · 01-23-2006, 03:03 AM

Keep the fuel air mixture right and the engine will be just fine. I'm going to avoid radical cams and big bore kits. The lower end could probably take the big bore kit, but I'm happy with the carb and exhaust mods I've made. Reliability rather than max power is my main goal and so far the TBA has been perfect on the road. Not the biggest, not the fastest, but the most reliable bike to date.

jeffrey1 · 01-23-2006, 08:36 PM

True and true now that i think about your posts you are right. When i first looked at the speedmaster My mechanic told me that those engines are bullet-proof and give little to no trouble . and what we were doing to those 2 stroke engines was leaning and clutching ,porting the heads with a dremal to get the most speed for weekend lake racing and repairing all the next week what we blew up But lean was the key word here which builds power and speed but not for long on those sled engines..they went like stink but tooooo expensive a hobby We spent more time pulling plugs to check if they were to lean than what we did riding. So thanks guys for your prospective

panda · 01-24-2006, 04:12 PM

the power increase from mild tuning will do no harm at all.. and if you learn to ride smoothly you should expect 100k from it. I do not know the power levels that the new bonnie were built to withstand, but expect it to have at least a 50% safety margin. For instance, the new indian built enfield with its lean burn 500cc single was built to run at 45bhp. they leave the factory with 25 ( there is an optional 'touring kit, basically jets and silencer) that take it out to 31bhp. Some double this power and they still run well