Service Bulletin:
H1 Drive chain
OriginalDate: 2005-08-05; Update: 2006-09-04
Bulletin No. H-5 | H1 DRIVE CHAIN | August 22, 1971
500 H1 Drive Chain
After frame No. 42003 the H1 carries a new heavier duty chain: EK50SH-T. This is an ENUMA chain which is stronger than the previous chain: DID50HDS. The new chain can be used on any H1 regardless of the frame number. NOTE: The master link for the new chain will not fit the old type chain and vice-versa. The dimensional differences in the two chains are illustrated below, all other critical dimensions are the same.
| New Type | Old Type | |
|---|---|---|
| Drive Chain Ass'y | 92057-009 | 92057-005 |
| Drive Chain Joint Ass'y | 92058-015 | 92058-012 |
| Chain Type (Identification) | EK 50SH-T | DID 50HDS |
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When using the new type chain assembly, care must be taken in mounting the chain guard, because the overall width of the new chain is greater. The guard must be mounted outside of the swing arm dust cover cap as illustrated below. Failure to mount the guard properly will allow the chain to hit the chain guard and the master link clip will be knocked off by the chain guard when the motorcycle is rolled backward.
| INCORRECT | CORRECT |
|---|---|
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