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Discussion Starter #1
as most of you know i bought a used 87 A/C jag 440, with only 1000 miles, and i have been working out the bugs in it, "mostly small stuff" gas cap leaking, burned out lights and stuff like that but one problem has me stumped, it only reaches a top speed of 55 mph, i have the orignial shop manual and it says check the belt for strech, its a brand new belt i just put it on and its definatly the right belt for the sled as 3 parts books list it for the sled!, this sled runs great starts right up clutch engages at about 3300 rpm and the engine revs to about 6500 no tach but i can tell by sound ,"worked around cars 30+ years"for the top speed, and it dosent waste any time getting there either, so i did what i know to do, adjust the track, theres about 11/4" freeplay in the track center with a 20 lb weight, as factory spec, new belt, the brake is free so its not hanging up, the sled is totally stock so im pretty sure they didnt gear down the chain case, "that would be highly unlikely" im starting to suspect it could be the drive clutch or secondary clutch, but with only 1000 miles? it has been stored inside all its life and is in brand new condition, so what gives? ive been told it should run 85 to 90 mph, not sure i need to be going that fast but id like the sled to run better than 50, any savy sled mechanics with a idea, i will gladly listen because the factory manual dosent address my problem.

if its not a CAT, then it must be a dog!
 

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85 90? sounds slight bit high. 85 sounds about right for a 440 Jag. I don't knoe it is a fancooled 440. So you don't have a speedo(I am guessing that is what you call a tach, car experience helped that huh?) and are just guessing the speed? How high in the clutch is the belt riding? if it doesn't ride up in the clutch far that will affect your performance. Shift the outer sheave on the secondary clutch and alittle and push in. slide the belt outwards first and try and see how the belt is riding up. If it is low on the sheave(not near the top) it will lose plenty of top end. Maybe you have the right size belt just not the right width? I don't know check it out.
 

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Maybe i should have stated 6500 sounds a little low to me?Just a thought?I'm not sure what the full shift out is either maybe someone that know could reply with that exact #"S.

Vmaxyam
 

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i would expect to see 85 from this 440 jag. As was said earlier, make sure your secondary clutch has the belt riding in the correct position. Also take a permenent marker and color the faces of your clutches. And make sure the marker all wears off to assure that your clutches are working properly. Make a few marks on the clutch faces that go from the center of the clutch face all the way to the outside of the face. If the mark wears off then your clutches are working properly. And like the other person said, check to make sure that your throttle slide is fully opening up. You should check this on the engine side of the carb.

Polaris is my way out - Other people just use a door.
 

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Discussion Starter #7
thanks tri, now theres a savvy sled guy!! , i was thinking how in the hell am i gonna check to make sure the belt is riding all the way up the sheave, but the permanant marker idea is great ! now ill be able to tell, was trying to figure how i was gonna check that, the people here are really smart, i gotta give them credit ! also my sled does have a spedo, and i feel that it is pretty accurate, but it doesent have a tach but im just guessing my rpms, as for top end RPM the manual lists it at between 6000- 6200, and that sounds just about where the sled is running at full throttle. thanks i will try your ideas!

if its not a CAT, then it must be a dog!
 

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um, Im not too sure on that 85 Triumph, I would guess.... 70 at the highest for that old of a fan cooled figuring the Liquid cooled 440's today will only do 80-85

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Ride Snowmobiles; baseball, bowling, and golf require only ONE ball!!
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Actually, I really am not too sure on the low RPM's on that sled.... Not quite into the groove of things yet today....
ok i feel better....lol

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Ride Snowmobiles; baseball, bowling, and golf require only ONE ball!!
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Well my speed guestimate is from an 89 Jag 440. My uncle owns it, and i rode with him for a while last year. Both the speedo on the Jag and the speedo on my Triumph read 85 mph. Now mind you this was on a lake with a very long flat run on hard pack snow.
On a side note, my uncle thought he was the shit when he hit 85 mph.....but i showed him wat the Triumph could do....lmao

Polaris is my way out - Other people just use a door.
 

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Gotta love those baby triples on the lake. As soon as they think they got ya, BAM! You take off like a bat outta hell. As for the Jag, his speedo could be just a wee bit off....

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Ride Snowmobiles; baseball, bowling, and golf require only ONE ball!!
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Discussion Starter #12
id say no one the spedo being off, i can for sure tell the diffrance between 50 and 85 !

if its not a CAT, then it must be a dog!
 

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It sounds like clutching to me too!But also check the trottle opening. and that sled in fine shape will do 85mph

Spaceman
Mean Green Racing
Elyria, Ohio
 

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Greetings vetboy: I have an '87 340 Jag that I too bought 'cause it was too good to pass up ( 285 miles ).

While I cursed the "unvarnishing" of the carb, and replacing all of the plastic tubing, oil and fuel tank exit fittings, it's still a nice old sled, even with front leaf springs.

The 340 will do about 60 m.p.h., even after sitting for 9 years.

Personally. I agree with most of the posters here, I would check the clutches. The PERMANENT marker method is great, and I would get the alaignment checked too. If there is too much deflection, the motor won't be able to achieve max. r.p.m. either.

(o;

DNO.
 
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