Primary Drive Chain Replacement & Tensioner Modification
- GL1000K1dan
- Posts: 34
- Joined: Thu Aug 09, 2018 3:26 am
- Location: England
- Motorcycle: 1976 GL1000 K1
Primary Drive Chain Replacement & Tensioner Modification
I am about to split the 2 halves of my GL1000 engine apart so that I can replace the Primary Drive Chain and replace the Chain Tensioner with the sping loaded GL1200 Tensioner. My reason for attempting this task was to try and eliminate the 'diesel' clatter that I can hear when the engine is ticking over at idle.
Could anyone give me some advice on what to look for in general, or check/replace certain components while I have the engine open.
I have seen some good stuff regarding trimming the Oil Thrower Plate to assist refitting the engine casing but if anyone could give me further advice then that would be great.
Could anyone give me some advice on what to look for in general, or check/replace certain components while I have the engine open.
I have seen some good stuff regarding trimming the Oil Thrower Plate to assist refitting the engine casing but if anyone could give me further advice then that would be great.
- WingAdmin
- Site Admin
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- Location: Strongsville, OH
- Motorcycle: 2000 GL1500 SE
1982 GL1100A Aspencade (sold)
1989 PC800 (sold)
1998 XV250 Virago (sold)
2012 Suzuki Burgman 400 (wife's!)
2007 Aspen Sentry Trailer
Re: Primary Drive Chain Replacement & Tensioner Modification
Before you go into this massive effort, have you balanced the carbs? Unbalanced carbs are the main cause of primary chain rattle. Even a tiny difference in carb balance can do it. Also check compression, look for differential between cylinders. If the cylinders are not producing exactly the same amount of power, it sets up resonant pulses that cause that chain rattle.GL1000K1dan wrote: ↑Tue Mar 03, 2020 2:35 pm I am about to split the 2 halves of my GL1000 engine apart so that I can replace the Primary Drive Chain and replace the Chain Tensioner with the sping loaded GL1200 Tensioner. My reason for attempting this task was to try and eliminate the 'diesel' clatter that I can hear when the engine is ticking over at idle.
Could anyone give me some advice on what to look for in general, or check/replace certain components while I have the engine open.
I have seen some good stuff regarding trimming the Oil Thrower Plate to assist refitting the engine casing but if anyone could give me further advice then that would be great.
- GL1000K1dan
- Posts: 34
- Joined: Thu Aug 09, 2018 3:26 am
- Location: England
- Motorcycle: 1976 GL1000 K1
Re: Primary Drive Chain Replacement & Tensioner Modification
I have had the carbs refurbished by Wingovations. The ignition and static timings are, as far as my ‘expertise’ extends are both good. Both compression and leak checks carried out with good readings from all. Carbs rebalanced and re checked 2 more times. Alas, I still have the dreaded rattle.
Now, it could be that I do not have the necessary ‘honed skills‘ to get all the above spot on but I have done my best. Removing and stripping the engine is drastic but I wanted to eliminate any possible internal issues - hence the primary chain and tensioner replacement, along with the starter chain replacement. I have all the gaskets and seals, and a great selection of different size hammers to get the engine apart
I am at a stage where I need to split the 2 halves of the casing. I anticipate this is going to be the most difficult task of the engine strip down. I have attacked the split line with judicial use of a hide faced mallet but it appears, at this stage, welded together. Of course I do not want to damage the casings so if anyone could give advice on the best way to separate the 2 halves then this would be welcome.
Now, it could be that I do not have the necessary ‘honed skills‘ to get all the above spot on but I have done my best. Removing and stripping the engine is drastic but I wanted to eliminate any possible internal issues - hence the primary chain and tensioner replacement, along with the starter chain replacement. I have all the gaskets and seals, and a great selection of different size hammers to get the engine apart
I am at a stage where I need to split the 2 halves of the casing. I anticipate this is going to be the most difficult task of the engine strip down. I have attacked the split line with judicial use of a hide faced mallet but it appears, at this stage, welded together. Of course I do not want to damage the casings so if anyone could give advice on the best way to separate the 2 halves then this would be welcome.
- dingdong
- Posts: 4025
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- Motorcycle: 1976 gl1000
1993 gl1500A
2004 NRX1800 Rune SOLD
Re: Primary Drive Chain Replacement & Tensioner Modification
Reinstall a few of the case bolts almost all the way. Leave about 2 or 3 mm space between bolt head and the case. Tap on the bolt heads to break loose.
- GL1000K1dan
- Posts: 34
- Joined: Thu Aug 09, 2018 3:26 am
- Location: England
- Motorcycle: 1976 GL1000 K1
Re: Primary Drive Chain Replacement & Tensioner Modification
Pics of the very slack P D Chain.
- WingAdmin
- Site Admin
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- Motorcycle: 2000 GL1500 SE
1982 GL1100A Aspencade (sold)
1989 PC800 (sold)
1998 XV250 Virago (sold)
2012 Suzuki Burgman 400 (wife's!)
2007 Aspen Sentry Trailer
Re: Primary Drive Chain Replacement & Tensioner Modification
Wow....that chain was sloppy like a wet noodle! Good job fixing it, the bike looks great!
- GL1000K1dan
- Posts: 34
- Joined: Thu Aug 09, 2018 3:26 am
- Location: England
- Motorcycle: 1976 GL1000 K1
Re: Primary Drive Chain Replacement & Tensioner Modification
It's rather puzzling why the Primary Drive Chain (PDC) should have stretched so much.
On stripping the engine it was evident that one of the cylinder heads had been removed and refitted (evidenced by way too much gasket sealant used by the PO) but I'm not sure if there is any connection/relation to the slack PDC.
The starter motor drive chain was also very sloppy but I replaced this at the same as the PDC.
Mileage on the clock is approx. 54000 which, according to the previous owner, is genuine. However, maybe I should suspect that this was not the truth and, possibly, the bike has a higher mileage.
The condition of the barrels, pistons, crank and camshafts were all good so I guess I'll never really know what the true mileage is.
Thanks WingAdmin for your generous comment on the bike.
On stripping the engine it was evident that one of the cylinder heads had been removed and refitted (evidenced by way too much gasket sealant used by the PO) but I'm not sure if there is any connection/relation to the slack PDC.
The starter motor drive chain was also very sloppy but I replaced this at the same as the PDC.
Mileage on the clock is approx. 54000 which, according to the previous owner, is genuine. However, maybe I should suspect that this was not the truth and, possibly, the bike has a higher mileage.
The condition of the barrels, pistons, crank and camshafts were all good so I guess I'll never really know what the true mileage is.
Thanks WingAdmin for your generous comment on the bike.
- landisr
- Posts: 787
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- Location: Gilbert, AZ
- Motorcycle: 1976 GL1000
1976 GL1000LTD
1994 GL1500A
Re: Primary Drive Chain Replacement & Tensioner Modification
Congrats on a job well done. You are much more brave and skilled than me. 
Pretty bike.
Ron in AZ
Pretty bike.
Ron in AZ
I'm not so sure about an inner child, but I have an inner idiot that surfaces every now and then.. 

- GL1000K1dan
- Posts: 34
- Joined: Thu Aug 09, 2018 3:26 am
- Location: England
- Motorcycle: 1976 GL1000 K1
Re: Primary Drive Chain Replacement & Tensioner Modification
Thanks Ron.
I just followed the Haynes Manual and the great advice from members of this GL1000 forum. Also Randakks and Wingovations.
I just followed the Haynes Manual and the great advice from members of this GL1000 forum. Also Randakks and Wingovations.
- Maz
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- Motorcycle: 1975 GL1000K1
1976 CB500T
1979 CB750L
1990 Yamaha FJ1200
1993 Suzuki GS500E
Re: Primary Drive Chain Replacement & Tensioner Modification
Nice work, Dan.
Nice looking bike too....but I guess I'm biased. I look forward to seeing you out on the road sometime.
Maz
Nice looking bike too....but I guess I'm biased. I look forward to seeing you out on the road sometime.
Maz
Ironically, Common Sense is the LEAST common of all senses!
- GL1000K1dan
- Posts: 34
- Joined: Thu Aug 09, 2018 3:26 am
- Location: England
- Motorcycle: 1976 GL1000 K1
Re: Primary Drive Chain Replacement & Tensioner Modification
Hey Maz
Hopefully this summer. I need a well sorted GL1000 to compare against. It's the cable runs that I need to check to ensure mine are routed correctly.
Hopefully this summer. I need a well sorted GL1000 to compare against. It's the cable runs that I need to check to ensure mine are routed correctly.
-
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1979 GL1000 - Contact:
Re: Primary Drive Chain Replacement & Tensioner Modification
I had a '79 into me (WinGovations) for a rattle with supposedly just 38k miles and the drive chain was just as bad as yours was. It rattled even though the 79 has a sprung tension factory fitted. Although the bores etc looked good, I still think it was at 138k.
'Impossible' is just a level of difficulty! The only stupid question is the one you didn't ask first!
( Seriously, you haven't read all 115 pages of my http://www.wingovations.com website ??
)
( Seriously, you haven't read all 115 pages of my http://www.wingovations.com website ??
